Show device attach web intent picker dialog only if we have registered services.

chrome/browser/intents/device_attached_intent_source.cc

Index: chrome/browser/intents/device_attached_intent_source.cc
diff --git a/chrome/browser/intents/device_attached_intent_source.cc b/chrome/browser/intents/device_attached_intent_source.cc
index 344a11324c657c51e16b3bfaeda37a6cd4b888d4..4f3a708c20e9e39998a888658aca91e61445f254 100644
--- a/chrome/browser/intents/device_attached_intent_source.cc
+++ b/chrome/browser/intents/device_attached_intent_source.cc
@@ -6,8 +6,14 @@
 
 #include <string>
 
+#include "base/bind.h"
 #include "base/file_path.h"
+#include "base/string16.h"
+#include "base/memory/ref_counted.h"
 #include "base/utf_string_conversions.h"
+#include "chrome/browser/intents/web_intents_registry.h"
+#include "chrome/browser/intents/web_intents_registry_factory.h"
+#include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "content/public/browser/web_intents_dispatcher.h"
@@ -15,6 +21,7 @@
 #include "webkit/fileapi/file_system_types.h"
 #include "webkit/fileapi/isolated_context.h"
 #include "webkit/glue/web_intent_data.h"
+#include "webkit/glue/web_intent_service_data.h"
 #include "webkit/fileapi/media/media_file_system_config.h"
 
 #if defined(SUPPORT_MEDIA_FILESYSTEM)
@@ -25,6 +32,53 @@ using fileapi::MediaDeviceMapService;
 
 using base::SystemMonitor;
 using content::WebContentsDelegate;
+using webkit_glue::WebIntentServiceData;
+
+namespace {
+
+// Specifies device attached web intent action.
+const string16 action(ASCIIToUTF16("chrome-extension://attach"));

[James Hawkins, 2012/08/06 16:36:36]

Don't we currently have this defined somewhere else as well?

[kmadhusu, 2012/08/06 18:11:52]

No. 

[kmadhusu, 2012/08/06 18:11:52]

Due to the construction of "string16" global object, I was receiving an exit
time destructor compile error on Mac Clang build. Therefore, I changed this
declaration. 

Ref:
http://build.chromium.org/p/tryserver.chromium/builders/mac/builds/2881/steps...

+
+// Specifies device attached web intent type.
+const string16 intent_type(ASCIIToUTF16("chrome-extension://filesystem"));
+
+// Dispatch intent only when there is a list of registered services. This is a
+// helper class that stores the attached media device information and decides
+// whether to dispatch an intent or not.
+class DispatchIntentTaskHelper
+    : public base::RefCountedThreadSafe<DispatchIntentTaskHelper> {
+ public:
+  DispatchIntentTaskHelper(
+      const base::WeakPtr<DeviceAttachedIntentSource> source,
+      SystemMonitor::MediaDeviceInfo device_info)
+      : source_(source),
+        device_info_(device_info) {
+  }
+
+  // Query callback for WebIntentsRegistry::GetIntentServices function.
+  void MayDispatchIntentForService(
+      const std::vector<WebIntentServiceData>& services) {
+    if (!services.empty() && source_)
+      source_->DispatchIntentsForService(device_info_);
+  }
+
+ private:
+  friend class base::RefCountedThreadSafe<DispatchIntentTaskHelper>;
+
+  ~DispatchIntentTaskHelper() {}
+
+  // Store a weak pointer to |DeviceAttachedIntentSource| object to dispatch a

[James Hawkins, 2012/08/06 16:36:36]

nit: Don't use imperative sentences to document member variables, i.e.,

// A weak pointer to |...|

[kmadhusu, 2012/08/06 18:11:52]

Done.

+  // web intent.
+  base::WeakPtr<DeviceAttachedIntentSource> source_;
+
+  // Store the device info. This is used while registering the device as file
+  // system.
+  const SystemMonitor::MediaDeviceInfo device_info_;
+
+  DISALLOW_COPY_AND_ASSIGN(DispatchIntentTaskHelper);
+};
+
+}  // namespace
 
 DeviceAttachedIntentSource::DeviceAttachedIntentSource(
     Browser* browser, WebContentsDelegate* delegate)
@@ -43,14 +97,18 @@ DeviceAttachedIntentSource::~DeviceAttachedIntentSource() {
 void DeviceAttachedIntentSource::OnMediaDeviceAttached(
     const std::string& id,
     const string16& name,
-    base::SystemMonitor::MediaDeviceType type,
+    base::SystemMonitor::MediaDeviceType device_type,
     const FilePath::StringType& location) {
   if (!browser_->window()->IsActive())
     return;
 
+  // TODO(kmadhusu): Dispatch intents on incognito window.
+  if (browser_->profile()->IsOffTheRecord())
+    return;
+
   // Only handle FilePaths for now.
   // TODO(kmadhusu): Handle all device types. http://crbug.com/140353.
-  if (type != SystemMonitor::TYPE_PATH)
+  if (device_type != SystemMonitor::TYPE_PATH)
     return;
 
   // Sanity checks for |device_path|.
@@ -58,24 +116,30 @@ void DeviceAttachedIntentSource::OnMediaDeviceAttached(
   if (!device_path.IsAbsolute() || device_path.ReferencesParent())
     return;
 
+  SystemMonitor::MediaDeviceInfo device_info(id, name, device_type, location);
+  scoped_refptr<DispatchIntentTaskHelper> task = new DispatchIntentTaskHelper(
+      AsWeakPtr(), device_info);
+  WebIntentsRegistryFactory::GetForProfile(browser_->profile())->
+      GetIntentServices(action, intent_type,
+          base::Bind(&DispatchIntentTaskHelper::MayDispatchIntentForService,

[James Hawkins, 2012/08/06 16:36:36]

nit: Start of parameter lines must align on the same column.

[kmadhusu, 2012/08/06 18:11:52]

Done.

+                     task.get()));
+}
+
+void DeviceAttachedIntentSource::DispatchIntentsForService(
+    const base::SystemMonitor::MediaDeviceInfo& device_info) {
   // Store the media device info locally.
-  SystemMonitor::MediaDeviceInfo device_info(id, name, type, location);
-  device_id_map_.insert(std::make_pair(id, device_info));
+  device_id_map_.insert(std::make_pair(device_info.unique_id, device_info));
 
-  std::string device_name(UTF16ToUTF8(name));
+  std::string device_name(UTF16ToUTF8(device_info.name));
+  const FilePath device_path(device_info.location);
 
-  // Register device path as an isolated file system.
   // TODO(kinuko, kmadhusu): Use a different file system type for MTP.
-  const std::string filesystem_id =
-      fileapi::IsolatedContext::GetInstance()->RegisterFileSystemForPath(
-          fileapi::kFileSystemTypeNativeMedia, device_path, &device_name);
-
-  CHECK(!filesystem_id.empty());
-  webkit_glue::WebIntentData intent(
-      ASCIIToUTF16("chrome-extension://attach"),
-      ASCIIToUTF16("chrome-extension://filesystem"),
-      device_name,
-      filesystem_id);
+  const std::string fs_id = fileapi::IsolatedContext::GetInstance()->
+      RegisterFileSystemForPath(fileapi::kFileSystemTypeNativeMedia,
+                                device_path, &device_name);
+
+  DCHECK(!fs_id.empty());
+  webkit_glue::WebIntentData intent(action, intent_type, device_name, fs_id);
 
   delegate_->WebIntentDispatch(NULL  /* no WebContents */,
                                content::WebIntentsDispatcher::Create(intent));