[DevTools] Split device discovery off DevToolsAnrdoidBridge.

chrome/browser/devtools/device/devtools_device_discovery.cc

Index: chrome/browser/devtools/device/devtools_device_discovery.cc
diff --git a/chrome/browser/devtools/device/devtools_android_bridge.cc b/chrome/browser/devtools/device/devtools_device_discovery.cc
similarity index 50%
copy from chrome/browser/devtools/device/devtools_android_bridge.cc
copy to chrome/browser/devtools/device/devtools_device_discovery.cc
index 229ef1967011c10b582aaa54efcdc03246e020c8..9436d34b6e1e6232d9caf0c96d817af49c50d127 100644
--- a/chrome/browser/devtools/device/devtools_android_bridge.cc
+++ b/chrome/browser/devtools/device/devtools_device_discovery.cc
@@ -2,217 +2,56 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/browser/devtools/device/devtools_android_bridge.h"
+#include "chrome/browser/devtools/device/devtools_device_discovery.h"
 
-#include <stddef.h>
-#include <algorithm>
-#include <map>
-#include <set>
-#include <utility>
-#include <vector>
-
-#include "base/base64.h"
 #include "base/bind.h"
-#include "base/command_line.h"
-#include "base/compiler_specific.h"
 #include "base/json/json_reader.h"
-#include "base/lazy_instance.h"
-#include "base/macros.h"
 #include "base/memory/ptr_util.h"
-#include "base/memory/singleton.h"
-#include "base/message_loop/message_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
-#include "base/threading/thread.h"
 #include "base/values.h"
-#include "chrome/browser/devtools/device/adb/adb_device_provider.h"
-#include "chrome/browser/devtools/device/port_forwarding_controller.h"
-#include "chrome/browser/devtools/device/tcp_device_provider.h"
-#include "chrome/browser/devtools/device/usb/usb_device_provider.h"
 #include "chrome/browser/devtools/devtools_protocol.h"
 #include "chrome/browser/devtools/devtools_window.h"
-#include "chrome/browser/devtools/remote_debugging_server.h"
-#include "chrome/browser/profiles/profile.h"
-#include "chrome/common/chrome_switches.h"
-#include "chrome/common/features.h"
-#include "chrome/common/pref_names.h"
-#include "components/keyed_service/content/browser_context_dependency_manager.h"
-#include "components/prefs/pref_service.h"
-#include "components/signin/core/browser/profile_oauth2_token_service.h"
-#include "components/signin/core/browser/signin_manager.h"
 #include "content/public/browser/devtools_agent_host.h"
 #include "content/public/browser/devtools_external_agent_proxy.h"
 #include "content/public/browser/devtools_external_agent_proxy_delegate.h"
 #include "content/public/browser/user_metrics.h"
 #include "net/base/escape.h"
-#include "net/base/host_port_pair.h"
-#include "net/base/net_errors.h"
-
-#if BUILDFLAG(ENABLE_SERVICE_DISCOVERY)
-#include "chrome/browser/devtools/device/cast_device_provider.h"
-#endif
 
 using content::BrowserThread;
 using content::DevToolsAgentHost;
+using RemoteBrowser = DevToolsDeviceDiscovery::RemoteBrowser;
+using RemoteDevice = DevToolsDeviceDiscovery::RemoteDevice;
+using RemotePage = DevToolsDeviceDiscovery::RemotePage;
 
 namespace {
 
 const char kPageListRequest[] = "/json";
 const char kVersionRequest[] = "/json/version";
 const char kClosePageRequest[] = "/json/close/%s";
-const char kNewPageRequestWithURL[] = "/json/new?%s";
 const char kActivatePageRequest[] = "/json/activate/%s";
 const char kBrowserTargetSocket[] = "/devtools/browser";
-const int kAdbPollingIntervalMs = 1000;
+const int kPollingIntervalMs = 1000;
 
 const char kPageReloadCommand[] = "Page.reload";
 
 const char kWebViewSocketPrefix[] = "webview_devtools_remote";
 
-const char kChromeDiscoveryURL[] = "localhost:9222";
-const char kNodeDiscoveryURL[] = "localhost:9229";
-
-bool BrowserIdFromString(const std::string& browser_id_str,
-                         std::string* serial,
-                         std::string* browser_id) {
-  size_t colon_pos = browser_id_str.find(':');
-  if (colon_pos == std::string::npos)
-    return false;
-  *serial = browser_id_str.substr(0, colon_pos);
-  *browser_id = browser_id_str.substr(colon_pos + 1);
-  return true;
-}
-
 static void NoOp(int, const std::string&) {}
 
-}  // namespace
-
-// DiscoveryRequest -----------------------------------------------------
-
-class DevToolsAndroidBridge::DiscoveryRequest
-    : public base::RefCountedThreadSafe<DiscoveryRequest,
-                                        BrowserThread::DeleteOnUIThread> {
- public:
-  DiscoveryRequest(AndroidDeviceManager* device_manager,
-                   const DeviceListCallback& callback);
- private:
-  friend struct BrowserThread::DeleteOnThread<BrowserThread::UI>;
-  friend class base::DeleteHelper<DiscoveryRequest>;
-  virtual ~DiscoveryRequest();
-
-  void ReceivedDevices(const AndroidDeviceManager::Devices& devices);
-  void ReceivedDeviceInfo(scoped_refptr<AndroidDeviceManager::Device> device,
-                          const AndroidDeviceManager::DeviceInfo& device_info);
-  void ReceivedVersion(scoped_refptr<RemoteBrowser>,
-                       int result,
-                       const std::string& response);
-  void ReceivedPages(scoped_refptr<AndroidDeviceManager::Device> device,
-                     scoped_refptr<RemoteBrowser>,
-                     int result,
-                     const std::string& response);
-
-  DeviceListCallback callback_;
-  CompleteDevices complete_devices_;
-};
-
-DevToolsAndroidBridge::DiscoveryRequest::DiscoveryRequest(
-    AndroidDeviceManager* device_manager,
-    const DeviceListCallback& callback)
-    : callback_(callback) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  device_manager->QueryDevices(
-      base::Bind(&DiscoveryRequest::ReceivedDevices, this));
-}
-
-DevToolsAndroidBridge::DiscoveryRequest::~DiscoveryRequest() {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  callback_.Run(complete_devices_);
-}
-
-void DevToolsAndroidBridge::DiscoveryRequest::ReceivedDevices(
-    const AndroidDeviceManager::Devices& devices) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  for (const auto& device : devices) {
-    device->QueryDeviceInfo(
-        base::Bind(&DiscoveryRequest::ReceivedDeviceInfo, this, device));
-  }
-}
-
-void DevToolsAndroidBridge::DiscoveryRequest::ReceivedDeviceInfo(
-    scoped_refptr<AndroidDeviceManager::Device> device,
-    const AndroidDeviceManager::DeviceInfo& device_info) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  scoped_refptr<RemoteDevice> remote_device =
-      new RemoteDevice(device->serial(), device_info);
-  complete_devices_.push_back(std::make_pair(device, remote_device));
-  for (RemoteBrowsers::iterator it = remote_device->browsers().begin();
-       it != remote_device->browsers().end(); ++it) {
-    device->SendJsonRequest(
-        (*it)->socket(),
-        kVersionRequest,
-        base::Bind(&DiscoveryRequest::ReceivedVersion, this, *it));
-    device->SendJsonRequest(
-        (*it)->socket(),
-        kPageListRequest,
-        base::Bind(&DiscoveryRequest::ReceivedPages, this, device, *it));
-  }
-}
-
-void DevToolsAndroidBridge::DiscoveryRequest::ReceivedVersion(
-    scoped_refptr<RemoteBrowser> browser,
-    int result,
-    const std::string& response) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  if (result < 0)
-    return;
-  // Parse version, append to package name if available,
-  std::unique_ptr<base::Value> value = base::JSONReader::Read(response);
-  base::DictionaryValue* dict;
-  if (value && value->GetAsDictionary(&dict)) {
-    std::string browser_name;
-    if (dict->GetString("Browser", &browser_name)) {
-      std::vector<std::string> parts = base::SplitString(
-          browser_name, "/", base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
-      if (parts.size() == 2)
-        browser->version_ = parts[1];
-      else
-        browser->version_ = browser_name;
-    }
-    std::string package;
-    if (dict->GetString("Android-Package", &package)) {
-      browser->display_name_ =
-          AndroidDeviceManager::GetBrowserName(browser->socket(), package);
-    }
-  }
-}
-
-void DevToolsAndroidBridge::DiscoveryRequest::ReceivedPages(
-    scoped_refptr<AndroidDeviceManager::Device> device,
-    scoped_refptr<RemoteBrowser> browser,
-    int result,
-    const std::string& response) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  if (result < 0)
-    return;
-  std::unique_ptr<base::Value> value = base::JSONReader::Read(response);
-  base::ListValue* list_value;
-  if (value && value->GetAsList(&list_value)) {
-    for (const auto& page_value : *list_value) {
-      base::DictionaryValue* dict;
-      if (page_value->GetAsDictionary(&dict))
-        browser->pages_.push_back(
-            new RemotePage(device, browser->browser_id_, *dict));
-    }
-  }
+static void ScheduleTaskDefault(const base::Closure& task) {
+  BrowserThread::PostDelayedTask(
+      BrowserThread::UI,
+      FROM_HERE,
+      task,
+      base::TimeDelta::FromMilliseconds(kPollingIntervalMs));
 }
 
 // ProtocolCommand ------------------------------------------------------------
 
-namespace {
-
 class ProtocolCommand
     : public AndroidDeviceManager::AndroidWebSocket::Delegate {
  public:
@@ -264,38 +103,9 @@ ProtocolCommand::~ProtocolCommand() {
     callback_.Run();
 }
 
-}  // namespace
-
-// static
-DevToolsAndroidBridge::Factory* DevToolsAndroidBridge::Factory::GetInstance() {
-  return base::Singleton<DevToolsAndroidBridge::Factory>::get();
-}
-
-// static
-DevToolsAndroidBridge* DevToolsAndroidBridge::Factory::GetForProfile(
-    Profile* profile) {
-  return static_cast<DevToolsAndroidBridge*>(GetInstance()->
-          GetServiceForBrowserContext(profile->GetOriginalProfile(), true));
-}
-
-DevToolsAndroidBridge::Factory::Factory()
-    : BrowserContextKeyedServiceFactory(
-          "DevToolsAndroidBridge",
-          BrowserContextDependencyManager::GetInstance()) {
-}
-
-DevToolsAndroidBridge::Factory::~Factory() {}
-
-KeyedService* DevToolsAndroidBridge::Factory::BuildServiceInstanceFor(
-    content::BrowserContext* context) const {
-  Profile* profile = Profile::FromBrowserContext(context);
-
-  return new DevToolsAndroidBridge(profile);
-}
-
 // AgentHostDelegate ----------------------------------------------------------
 
-class DevToolsAndroidBridge::AgentHostDelegate
+class AgentHostDelegate
     : public content::DevToolsExternalAgentProxyDelegate,
       public AndroidDeviceManager::AndroidWebSocket::Delegate {
  public:
@@ -399,7 +209,7 @@ static std::string GetTargetPath(base::DictionaryValue* value) {
 
 // static
 scoped_refptr<content::DevToolsAgentHost>
-DevToolsAndroidBridge::AgentHostDelegate::GetOrCreateAgentHost(
+AgentHostDelegate::GetOrCreateAgentHost(
     scoped_refptr<AndroidDeviceManager::Device> device,
     const std::string& browser_id,
     const std::string& local_id,
@@ -420,7 +230,7 @@ DevToolsAndroidBridge::AgentHostDelegate::GetOrCreateAgentHost(
   return result;
 }
 
-DevToolsAndroidBridge::AgentHostDelegate::AgentHostDelegate(
+AgentHostDelegate::AgentHostDelegate(
     scoped_refptr<AndroidDeviceManager::Device> device,
     const std::string& browser_id,
     const std::string& local_id,
@@ -444,11 +254,10 @@ DevToolsAndroidBridge::AgentHostDelegate::AgentHostDelegate(
       proxy_(nullptr) {
 }
 
-DevToolsAndroidBridge::AgentHostDelegate::~AgentHostDelegate() {
+AgentHostDelegate::~AgentHostDelegate() {
 }
 
-void DevToolsAndroidBridge::AgentHostDelegate::Attach(
-    content::DevToolsExternalAgentProxy* proxy) {
+void AgentHostDelegate::Attach(content::DevToolsExternalAgentProxy* proxy) {
   proxy_ = proxy;
   content::RecordAction(
       base::StartsWith(browser_id_, kWebViewSocketPrefix,
@@ -459,56 +268,55 @@ void DevToolsAndroidBridge::AgentHostDelegate::Attach(
       device_->CreateWebSocket(browser_id_, target_path_, this));
 }
 
-void DevToolsAndroidBridge::AgentHostDelegate::Detach() {
+void AgentHostDelegate::Detach() {
   web_socket_.reset();
   proxy_ = nullptr;
 }
 
-std::string DevToolsAndroidBridge::AgentHostDelegate::GetType() {
+std::string AgentHostDelegate::GetType() {
   return remote_type_;
 }
 
-std::string DevToolsAndroidBridge::AgentHostDelegate::GetTitle() {
+std::string AgentHostDelegate::GetTitle() {
   return title_;
 }
 
-std::string DevToolsAndroidBridge::AgentHostDelegate::GetDescription() {
+std::string AgentHostDelegate::GetDescription() {
   return description_;
 }
 
-GURL DevToolsAndroidBridge::AgentHostDelegate::GetURL() {
+GURL AgentHostDelegate::GetURL() {
   return url_;
 }
 
-GURL DevToolsAndroidBridge::AgentHostDelegate::GetFaviconURL() {
+GURL AgentHostDelegate::GetFaviconURL() {
   return favicon_url_;
 }
 
-std::string DevToolsAndroidBridge::AgentHostDelegate::GetFrontendURL() {
+std::string AgentHostDelegate::GetFrontendURL() {
   return frontend_url_;
 }
 
-bool DevToolsAndroidBridge::AgentHostDelegate::Activate() {
+bool AgentHostDelegate::Activate() {
   std::string request = base::StringPrintf(kActivatePageRequest,
                                            remote_id_.c_str());
   device_->SendJsonRequest(browser_id_, request, base::Bind(&NoOp));
   return true;
 }
 
-void DevToolsAndroidBridge::AgentHostDelegate::Reload() {
+void AgentHostDelegate::Reload() {
   SendProtocolCommand(target_path_, kPageReloadCommand, nullptr,
                       base::Closure());
 }
 
-bool DevToolsAndroidBridge::AgentHostDelegate::Close() {
+bool AgentHostDelegate::Close() {
   std::string request = base::StringPrintf(kClosePageRequest,
                                            remote_id_.c_str());
   device_->SendJsonRequest(browser_id_, request, base::Bind(&NoOp));
   return true;
 }
 
-void DevToolsAndroidBridge::AgentHostDelegate::SendMessageToBackend(
-    const std::string& message) {
+void AgentHostDelegate::SendMessageToBackend(const std::string& message) {
   // We could have detached due to physical connection being closed.
   if (!proxy_)
     return;
@@ -518,7 +326,7 @@ void DevToolsAndroidBridge::AgentHostDelegate::SendMessageToBackend(
     pending_messages_.push_back(message);
 }
 
-void DevToolsAndroidBridge::AgentHostDelegate::OnSocketOpened() {
+void AgentHostDelegate::OnSocketOpened() {
   socket_opened_ = true;
   for (std::vector<std::string>::iterator it = pending_messages_.begin();
        it != pending_messages_.end(); ++it) {
@@ -527,13 +335,12 @@ void DevToolsAndroidBridge::AgentHostDelegate::OnSocketOpened() {
   pending_messages_.clear();
 }
 
-void DevToolsAndroidBridge::AgentHostDelegate::OnFrameRead(
-    const std::string& message) {
+void AgentHostDelegate::OnFrameRead(const std::string& message) {
   if (proxy_)
       proxy_->DispatchOnClientHost(message);
 }
 
-void DevToolsAndroidBridge::AgentHostDelegate::OnSocketClosed() {
+void AgentHostDelegate::OnSocketClosed() {
   if (proxy_) {
     std::string message = "{ \"method\": \"Inspector.detached\", "
         "\"params\": { \"reason\": \"Connection lost.\"} }";
@@ -542,7 +349,7 @@ void DevToolsAndroidBridge::AgentHostDelegate::OnSocketClosed() {
   }
 }
 
-void DevToolsAndroidBridge::AgentHostDelegate::SendProtocolCommand(
+void AgentHostDelegate::SendProtocolCommand(
     const std::string& target_path,
     const std::string& method,
     std::unique_ptr<base::DictionaryValue> params,
@@ -556,9 +363,130 @@ void DevToolsAndroidBridge::AgentHostDelegate::SendProtocolCommand(
       callback);
 }
 
-// DevToolsAndroidBridge::RemotePage ------------------------------------------
+}  // namespace
+
+// DevToolsDeviceDiscovery::DiscoveryRequest ----------------------------------
+
+class DevToolsDeviceDiscovery::DiscoveryRequest
+    : public base::RefCountedThreadSafe<DiscoveryRequest,
+                                        BrowserThread::DeleteOnUIThread> {
+ public:
+  DiscoveryRequest(AndroidDeviceManager* device_manager,
+                   const DevToolsDeviceDiscovery::DeviceListCallback& callback);
+ private:
+  friend struct BrowserThread::DeleteOnThread<BrowserThread::UI>;
+  friend class base::DeleteHelper<DiscoveryRequest>;
+  virtual ~DiscoveryRequest();
+
+  void ReceivedDevices(const AndroidDeviceManager::Devices& devices);
+  void ReceivedDeviceInfo(scoped_refptr<AndroidDeviceManager::Device> device,
+                          const AndroidDeviceManager::DeviceInfo& device_info);
+  void ReceivedVersion(scoped_refptr<RemoteBrowser>,
+                       int result,
+                       const std::string& response);
+  void ReceivedPages(scoped_refptr<AndroidDeviceManager::Device> device,
+                     scoped_refptr<RemoteBrowser>,
+                     int result,
+                     const std::string& response);
+
+  DevToolsDeviceDiscovery::DeviceListCallback callback_;
+  DevToolsDeviceDiscovery::CompleteDevices complete_devices_;
+};
+
+DevToolsDeviceDiscovery::DiscoveryRequest::DiscoveryRequest(
+    AndroidDeviceManager* device_manager,
+    const DevToolsDeviceDiscovery::DeviceListCallback& callback)
+    : callback_(callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  device_manager->QueryDevices(
+      base::Bind(&DiscoveryRequest::ReceivedDevices, this));
+}
 
-DevToolsAndroidBridge::RemotePage::RemotePage(
+DevToolsDeviceDiscovery::DiscoveryRequest::~DiscoveryRequest() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  callback_.Run(complete_devices_);
+}
+
+void DevToolsDeviceDiscovery::DiscoveryRequest::ReceivedDevices(
+    const AndroidDeviceManager::Devices& devices) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  for (const auto& device : devices) {
+    device->QueryDeviceInfo(
+        base::Bind(&DiscoveryRequest::ReceivedDeviceInfo, this, device));
+  }
+}
+
+void DevToolsDeviceDiscovery::DiscoveryRequest::ReceivedDeviceInfo(
+    scoped_refptr<AndroidDeviceManager::Device> device,
+    const AndroidDeviceManager::DeviceInfo& device_info) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  scoped_refptr<RemoteDevice> remote_device =
+      new RemoteDevice(device->serial(), device_info);
+  complete_devices_.push_back(std::make_pair(device, remote_device));
+  for (RemoteBrowsers::iterator it = remote_device->browsers().begin();
+       it != remote_device->browsers().end(); ++it) {
+    device->SendJsonRequest(
+        (*it)->socket(),
+        kVersionRequest,
+        base::Bind(&DiscoveryRequest::ReceivedVersion, this, *it));
+    device->SendJsonRequest(
+        (*it)->socket(),
+        kPageListRequest,
+        base::Bind(&DiscoveryRequest::ReceivedPages, this, device, *it));
+  }
+}
+
+void DevToolsDeviceDiscovery::DiscoveryRequest::ReceivedVersion(
+    scoped_refptr<RemoteBrowser> browser,
+    int result,
+    const std::string& response) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  if (result < 0)
+    return;
+  // Parse version, append to package name if available,
+  std::unique_ptr<base::Value> value = base::JSONReader::Read(response);
+  base::DictionaryValue* dict;
+  if (value && value->GetAsDictionary(&dict)) {
+    std::string browser_name;
+    if (dict->GetString("Browser", &browser_name)) {
+      std::vector<std::string> parts = base::SplitString(
+          browser_name, "/", base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
+      if (parts.size() == 2)
+        browser->version_ = parts[1];
+      else
+        browser->version_ = browser_name;
+    }
+    std::string package;
+    if (dict->GetString("Android-Package", &package)) {
+      browser->display_name_ =
+          AndroidDeviceManager::GetBrowserName(browser->socket(), package);
+    }
+  }
+}
+
+void DevToolsDeviceDiscovery::DiscoveryRequest::ReceivedPages(
+    scoped_refptr<AndroidDeviceManager::Device> device,
+    scoped_refptr<RemoteBrowser> browser,
+    int result,
+    const std::string& response) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  if (result < 0)
+    return;
+  std::unique_ptr<base::Value> value = base::JSONReader::Read(response);
+  base::ListValue* list_value;
+  if (value && value->GetAsList(&list_value)) {
+    for (const auto& page_value : *list_value) {
+      base::DictionaryValue* dict;
+      if (page_value->GetAsDictionary(&dict))
+        browser->pages_.push_back(
+            new RemotePage(device, browser->browser_id_, *dict));
+    }
+  }
+}
+
+// DevToolsDeviceDiscovery::RemotePage ----------------------------------------
+
+DevToolsDeviceDiscovery::RemotePage::RemotePage(
     scoped_refptr<AndroidDeviceManager::Device> device,
     const std::string& browser_id,
     const base::DictionaryValue& dict)
@@ -567,11 +495,11 @@ DevToolsAndroidBridge::RemotePage::RemotePage(
       dict_(dict.DeepCopy()) {
 }
 
-DevToolsAndroidBridge::RemotePage::~RemotePage() {
+DevToolsDeviceDiscovery::RemotePage::~RemotePage() {
 }
 
 scoped_refptr<content::DevToolsAgentHost>
-DevToolsAndroidBridge::RemotePage::CreateTarget() {
+DevToolsDeviceDiscovery::RemotePage::CreateTarget() {
   std::string local_id = BuildUniqueTargetId(device_->serial(),
                                              browser_id_,
                                              dict_.get());
@@ -582,9 +510,9 @@ DevToolsAndroidBridge::RemotePage::CreateTarget() {
       device_, browser_id_, local_id, target_path, type, dict_.get());
 }
 
-// DevToolsAndroidBridge::RemoteBrowser ---------------------------------------
+// DevToolsDeviceDiscovery::RemoteBrowser -------------------------------------
 
-DevToolsAndroidBridge::RemoteBrowser::RemoteBrowser(
+DevToolsDeviceDiscovery::RemoteBrowser::RemoteBrowser(
     const std::string& serial,
     const AndroidDeviceManager::BrowserInfo& browser_info)
     : serial_(serial),
@@ -594,16 +522,16 @@ DevToolsAndroidBridge::RemoteBrowser::RemoteBrowser(
       type_(browser_info.type) {
 }
 
-bool DevToolsAndroidBridge::RemoteBrowser::IsChrome() {
+bool DevToolsDeviceDiscovery::RemoteBrowser::IsChrome() {
   return type_ == AndroidDeviceManager::BrowserInfo::kTypeChrome;
 }
 
-std::string DevToolsAndroidBridge::RemoteBrowser::GetId() {
+std::string DevToolsDeviceDiscovery::RemoteBrowser::GetId() {
   return serial() + ":" + socket();
 }
 
-DevToolsAndroidBridge::RemoteBrowser::ParsedVersion
-DevToolsAndroidBridge::RemoteBrowser::GetParsedVersion() {
+DevToolsDeviceDiscovery::RemoteBrowser::ParsedVersion
+DevToolsDeviceDiscovery::RemoteBrowser::GetParsedVersion() {
   ParsedVersion result;
   for (const base::StringPiece& part :
        base::SplitStringPiece(
@@ -615,62 +543,12 @@ DevToolsAndroidBridge::RemoteBrowser::GetParsedVersion() {
   return result;
 }
 
-scoped_refptr<content::DevToolsAgentHost>
-DevToolsAndroidBridge::GetBrowserAgentHost(
-    scoped_refptr<RemoteBrowser> browser) {
-  DeviceMap::iterator it = device_map_.find(browser->serial());
-  if (it == device_map_.end())
-    return nullptr;
-
-  return AgentHostDelegate::GetOrCreateAgentHost(
-      it->second,
-      browser->browser_id_,
-      "adb:" + browser->serial() + ":" + browser->socket(),
-      kBrowserTargetSocket, DevToolsAgentHost::kTypeBrowser, nullptr);
+DevToolsDeviceDiscovery::RemoteBrowser::~RemoteBrowser() {
 }
 
-void DevToolsAndroidBridge::SendJsonRequest(
-    const std::string& browser_id_str,
-    const std::string& url,
-    const JsonRequestCallback& callback) {
-  std::string serial;
-  std::string browser_id;
-  if (!BrowserIdFromString(browser_id_str, &serial, &browser_id)) {
-    callback.Run(net::ERR_FAILED, std::string());
-    return;
-  }
-  DeviceMap::iterator it = device_map_.find(serial);
-  if (it == device_map_.end()) {
-    callback.Run(net::ERR_FAILED, std::string());
-    return;
-  }
-  it->second->SendJsonRequest(browser_id, url, callback);
-}
-
-void DevToolsAndroidBridge::OpenRemotePage(scoped_refptr<RemoteBrowser> browser,
-                                           const std::string& input_url) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  GURL gurl(input_url);
-  if (!gurl.is_valid()) {
-    gurl = GURL("http://" + input_url);
-    if (!gurl.is_valid())
-      return;
-  }
-  std::string url = gurl.spec();
-  RemoteBrowser::ParsedVersion parsed_version = browser->GetParsedVersion();
+// DevToolsDeviceDiscovery::RemoteDevice --------------------------------------
 
-  std::string query = net::EscapeQueryParamValue(url, false /* use_plus */);
-  std::string request =
-      base::StringPrintf(kNewPageRequestWithURL, query.c_str());
-  SendJsonRequest(browser->GetId(), request, base::Bind(&NoOp));
-}
-
-DevToolsAndroidBridge::RemoteBrowser::~RemoteBrowser() {
-}
-
-// DevToolsAndroidBridge::RemoteDevice ----------------------------------------
-
-DevToolsAndroidBridge::RemoteDevice::RemoteDevice(
+DevToolsDeviceDiscovery::RemoteDevice::RemoteDevice(
     const std::string& serial,
     const AndroidDeviceManager::DeviceInfo& device_info)
     : serial_(serial),
@@ -685,294 +563,90 @@ DevToolsAndroidBridge::RemoteDevice::RemoteDevice(
   }
 }
 
-DevToolsAndroidBridge::RemoteDevice::~RemoteDevice() {
+DevToolsDeviceDiscovery::RemoteDevice::~RemoteDevice() {
 }
 
-// DevToolsAndroidBridge ------------------------------------------------------
+// DevToolsDeviceDiscovery ----------------------------------------------------
 
-// static
-void DevToolsAndroidBridge::QueryCompleteDevices(
+DevToolsDeviceDiscovery::DevToolsDeviceDiscovery(
     AndroidDeviceManager* device_manager,
-    const DeviceListCallback& callback) {
-  new DiscoveryRequest(device_manager, callback);
-}
-
-DevToolsAndroidBridge::DevToolsAndroidBridge(
-    Profile* profile)
-    : profile_(profile),
-      device_manager_(AndroidDeviceManager::Create()),
-      task_scheduler_(base::Bind(&DevToolsAndroidBridge::ScheduleTaskDefault)),
-      port_forwarding_controller_(new PortForwardingController(profile)),
+    const DeviceListCallback& callback)
+    : device_manager_(device_manager),
+      callback_(callback),
+      task_scheduler_(base::Bind(&ScheduleTaskDefault)),
       weak_factory_(this) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  pref_change_registrar_.Init(profile_->GetPrefs());
-  pref_change_registrar_.Add(prefs::kDevToolsDiscoverUsbDevicesEnabled,
-      base::Bind(&DevToolsAndroidBridge::CreateDeviceProviders,
-                 base::Unretained(this)));
-  pref_change_registrar_.Add(prefs::kDevToolsTCPDiscoveryConfig,
-      base::Bind(&DevToolsAndroidBridge::CreateDeviceProviders,
-                 base::Unretained(this)));
-  pref_change_registrar_.Add(prefs::kDevToolsDiscoverTCPTargetsEnabled,
-      base::Bind(&DevToolsAndroidBridge::CreateDeviceProviders,
-                 base::Unretained(this)));
-  base::ListValue* target_discovery = new base::ListValue();
-  target_discovery->AppendString(kChromeDiscoveryURL);
-  target_discovery->AppendString(kNodeDiscoveryURL);
-  profile->GetPrefs()->SetDefaultPrefValue(
-      prefs::kDevToolsTCPDiscoveryConfig, target_discovery);
-  CreateDeviceProviders();
-}
-
-void DevToolsAndroidBridge::AddDeviceListListener(
-    DeviceListListener* listener) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  bool polling_was_off = !NeedsDeviceListPolling();
-  device_list_listeners_.push_back(listener);
-  if (polling_was_off)
-    StartDeviceListPolling();
+  RequestDeviceList();
 }
 
-void DevToolsAndroidBridge::RemoveDeviceListListener(
-    DeviceListListener* listener) {
+DevToolsDeviceDiscovery::~DevToolsDeviceDiscovery() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  DeviceListListeners::iterator it = std::find(
-      device_list_listeners_.begin(), device_list_listeners_.end(), listener);
-  DCHECK(it != device_list_listeners_.end());
-  device_list_listeners_.erase(it);
-  if (!NeedsDeviceListPolling())
-    StopDeviceListPolling();
 }
 
-void DevToolsAndroidBridge::AddDeviceCountListener(
-    DeviceCountListener* listener) {
-  device_count_listeners_.push_back(listener);
-  if (device_count_listeners_.size() == 1)
-    StartDeviceCountPolling();
-}
-
-void DevToolsAndroidBridge::RemoveDeviceCountListener(
-    DeviceCountListener* listener) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  DeviceCountListeners::iterator it = std::find(
-      device_count_listeners_.begin(), device_count_listeners_.end(), listener);
-  DCHECK(it != device_count_listeners_.end());
-  device_count_listeners_.erase(it);
-  if (device_count_listeners_.empty())
-    StopDeviceCountPolling();
-}
-
-void DevToolsAndroidBridge::AddPortForwardingListener(
-    PortForwardingListener* listener) {
-  bool polling_was_off = !NeedsDeviceListPolling();
-  port_forwarding_listeners_.push_back(listener);
-  if (polling_was_off)
-    StartDeviceListPolling();
-}
-
-void DevToolsAndroidBridge::RemovePortForwardingListener(
-    PortForwardingListener* listener) {
-  PortForwardingListeners::iterator it = std::find(
-      port_forwarding_listeners_.begin(),
-      port_forwarding_listeners_.end(),
-      listener);
-  DCHECK(it != port_forwarding_listeners_.end());
-  port_forwarding_listeners_.erase(it);
-  if (!NeedsDeviceListPolling())
-    StopDeviceListPolling();
-}
-
-DevToolsAndroidBridge::~DevToolsAndroidBridge() {
+void DevToolsDeviceDiscovery::SetScheduler(
+    base::Callback<void(const base::Closure&)> scheduler) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  DCHECK(device_list_listeners_.empty());
-  DCHECK(device_count_listeners_.empty());
-  DCHECK(port_forwarding_listeners_.empty());
+  task_scheduler_ = scheduler;
 }
 
-void DevToolsAndroidBridge::StartDeviceListPolling() {
-  device_list_callback_.Reset(
-      base::Bind(&DevToolsAndroidBridge::ReceivedDeviceList, AsWeakPtr()));
-  RequestDeviceList(device_list_callback_.callback());
-}
-
-void DevToolsAndroidBridge::StopDeviceListPolling() {
-  device_list_callback_.Cancel();
-  device_map_.clear();
-  port_forwarding_controller_->CloseAllConnections();
-}
-
-bool DevToolsAndroidBridge::NeedsDeviceListPolling() {
-  return !device_list_listeners_.empty() || !port_forwarding_listeners_.empty();
+// static
+scoped_refptr<content::DevToolsAgentHost>
+DevToolsDeviceDiscovery::CreateBrowserAgentHost(
+    scoped_refptr<AndroidDeviceManager::Device> device,
+    scoped_refptr<RemoteBrowser> browser) {
+  return AgentHostDelegate::GetOrCreateAgentHost(
+      device,
+      browser->browser_id_,
+      "adb:" + browser->serial() + ":" + browser->socket(),
+      kBrowserTargetSocket, DevToolsAgentHost::kTypeBrowser, nullptr);
 }
 
-void DevToolsAndroidBridge::RequestDeviceList(
-    const DeviceListCallback& callback) {
+void DevToolsDeviceDiscovery::RequestDeviceList() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-
-  if (!NeedsDeviceListPolling() ||
-      !callback.Equals(device_list_callback_.callback()))
-    return;
-
-  new DiscoveryRequest(device_manager_.get(), callback);
+  new DiscoveryRequest(
+      device_manager_,
+      base::Bind(&DevToolsDeviceDiscovery::ReceivedDeviceList,
+                 weak_factory_.GetWeakPtr()));
 }
 
-void DevToolsAndroidBridge::ReceivedDeviceList(
+void DevToolsDeviceDiscovery::ReceivedDeviceList(
     const CompleteDevices& complete_devices) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-
-  device_map_.clear();
-  RemoteDevices remote_devices;
-  for (const auto& pair : complete_devices) {
-    device_map_[pair.first->serial()] = pair.first;
-    remote_devices.push_back(pair.second);
-  }
-
-  DeviceListListeners copy(device_list_listeners_);
-  for (DeviceListListeners::iterator it = copy.begin(); it != copy.end(); ++it)
-    (*it)->DeviceListChanged(remote_devices);
-
-  ForwardingStatus status =
-      port_forwarding_controller_->DeviceListChanged(complete_devices);
-  PortForwardingListeners forwarding_listeners(port_forwarding_listeners_);
-  for (PortForwardingListeners::iterator it = forwarding_listeners.begin();
-       it != forwarding_listeners.end(); ++it) {
-    (*it)->PortStatusChanged(status);
-  }
-
-  if (!NeedsDeviceListPolling())
-    return;
-
-  task_scheduler_.Run(
-      base::Bind(&DevToolsAndroidBridge::RequestDeviceList,
-                 AsWeakPtr(), device_list_callback_.callback()));
-}
-
-void DevToolsAndroidBridge::StartDeviceCountPolling() {
-  device_count_callback_.Reset(
-      base::Bind(&DevToolsAndroidBridge::ReceivedDeviceCount, AsWeakPtr()));
-  RequestDeviceCount(device_count_callback_.callback());
-}
-
-void DevToolsAndroidBridge::StopDeviceCountPolling() {
-  device_count_callback_.Cancel();
+  task_scheduler_.Run(base::Bind(&DevToolsDeviceDiscovery::RequestDeviceList,
+                                 weak_factory_.GetWeakPtr()));
+  // |callback_| should be run last as it may destroy |this|.
+  callback_.Run(complete_devices);
 }
 
-void DevToolsAndroidBridge::RequestDeviceCount(
-    const base::Callback<void(int)>& callback) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-
-  if (device_count_listeners_.empty() ||
-      !callback.Equals(device_count_callback_.callback()))
-    return;
+namespace {
 
-  UsbDeviceProvider::CountDevices(callback);
-}
+class OnceWrapper {
+ public:
+  OnceWrapper(AndroidDeviceManager* device_manager,
+              const DevToolsDeviceDiscovery::DeviceListCallback& callback)
+      : callback_(callback) {
+    discovery_.reset(new DevToolsDeviceDiscovery(device_manager,
+         base::Bind(&OnceWrapper::Callback, base::Unretained(this))));
+    discovery_->SetScheduler(base::Bind(&OnceWrapper::NoOp));
+  }
 
-void DevToolsAndroidBridge::ReceivedDeviceCount(int count) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+ private:
+  static void NoOp(const base::Closure&) {}
 
-  DeviceCountListeners copy(device_count_listeners_);
-  for (DeviceCountListeners::iterator it = copy.begin(); it != copy.end(); ++it)
-    (*it)->DeviceCountChanged(count);
+  void Callback(const DevToolsDeviceDiscovery::CompleteDevices& devices) {
+    callback_.Run(devices);
+    delete this;
+  }
 
-  if (device_count_listeners_.empty())
-     return;
+  std::unique_ptr<DevToolsDeviceDiscovery> discovery_;
+  const DevToolsDeviceDiscovery::DeviceListCallback callback_;
+};
 
-  task_scheduler_.Run(
-      base::Bind(&DevToolsAndroidBridge::RequestDeviceCount,
-                 AsWeakPtr(), device_count_callback_.callback()));
-}
+} // namespace
 
 // static
-void DevToolsAndroidBridge::ScheduleTaskDefault(const base::Closure& task) {
-  BrowserThread::PostDelayedTask(
-      BrowserThread::UI,
-      FROM_HERE,
-      task,
-      base::TimeDelta::FromMilliseconds(kAdbPollingIntervalMs));
-}
-
-static std::set<net::HostPortPair> ParseTargetDiscoveryPreferenceValue(
-    const base::ListValue* preferenceValue) {
-  std::set<net::HostPortPair> targets;
-  if (!preferenceValue || preferenceValue->empty())
-    return targets;
-  std::string address;
-  for (size_t i = 0; i < preferenceValue->GetSize(); i++) {
-    if (!preferenceValue->GetString(i, &address))
-      continue;
-    net::HostPortPair target = net::HostPortPair::FromString(address);
-    if (target.IsEmpty()) {
-      LOG(WARNING) << "Invalid target: " << address;
-      continue;
-    }
-    targets.insert(target);
-  }
-  return targets;
-}
-
-static scoped_refptr<TCPDeviceProvider> CreateTCPDeviceProvider(
-    const base::ListValue* targetDiscoveryConfig) {
-  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
-  std::set<net::HostPortPair> targets =
-      ParseTargetDiscoveryPreferenceValue(targetDiscoveryConfig);
-  if (targets.empty() &&
-      !command_line->HasSwitch(switches::kRemoteDebuggingTargets))
-    return nullptr;
-  std::string value =
-      command_line->GetSwitchValueASCII(switches::kRemoteDebuggingTargets);
-  std::vector<std::string> addresses = base::SplitString(
-      value, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
-  for (const std::string& address : addresses) {
-    net::HostPortPair target = net::HostPortPair::FromString(address);
-    if (target.IsEmpty()) {
-      LOG(WARNING) << "Invalid target: " << address;
-      continue;
-    }
-    targets.insert(target);
-  }
-  if (targets.empty())
-    return nullptr;
-  return new TCPDeviceProvider(targets);
-}
-
-void DevToolsAndroidBridge::CreateDeviceProviders() {
-  AndroidDeviceManager::DeviceProviders device_providers;
-  PrefService* service = profile_->GetPrefs();
-  const base::ListValue* targets =
-      service->GetBoolean(prefs::kDevToolsDiscoverTCPTargetsEnabled)
-          ? service->GetList(prefs::kDevToolsTCPDiscoveryConfig)
-          : nullptr;
-  scoped_refptr<TCPDeviceProvider> provider = CreateTCPDeviceProvider(targets);
-  if (tcp_provider_callback_)
-    tcp_provider_callback_.Run(provider);
-
-  if (provider)
-    device_providers.push_back(provider);
-
-#if BUILDFLAG(ENABLE_SERVICE_DISCOVERY)
-  device_providers.push_back(new CastDeviceProvider());
-#endif
-
-  device_providers.push_back(new AdbDeviceProvider());
-
-  const PrefService::Preference* pref =
-      service->FindPreference(prefs::kDevToolsDiscoverUsbDevicesEnabled);
-  const base::Value* pref_value = pref->GetValue();
-
-  bool enabled;
-  if (pref_value->GetAsBoolean(&enabled) && enabled) {
-    device_providers.push_back(new UsbDeviceProvider(profile_));
-  }
-
-  device_manager_->SetDeviceProviders(device_providers);
-  if (NeedsDeviceListPolling()) {
-    StopDeviceListPolling();
-    StartDeviceListPolling();
-  }
-}
-
-void DevToolsAndroidBridge::set_tcp_provider_callback_for_test(
-    TCPProviderCallback callback) {
-  tcp_provider_callback_ = callback;
-  CreateDeviceProviders();
+void DevToolsDeviceDiscovery::DiscoverOnce(
+    AndroidDeviceManager* device_manager,
+    const DeviceListCallback& callback) {
+  new OnceWrapper(device_manager, callback);
 }