<webview>: First stab at implementing media permission request for guests.

content/browser/browser_plugin/browser_plugin_guest.cc

Index: content/browser/browser_plugin/browser_plugin_guest.cc
diff --git a/content/browser/browser_plugin/browser_plugin_guest.cc b/content/browser/browser_plugin/browser_plugin_guest.cc
index 3042c7361fbc9d8057ce3bab1a9a568dfa8bfb97..00b7a3c583635e5cd27eafc9454e0849c7d6f2c0 100644
--- a/content/browser/browser_plugin/browser_plugin_guest.cc
+++ b/content/browser/browser_plugin/browser_plugin_guest.cc
@@ -17,8 +17,8 @@
 #include "content/common/browser_plugin_messages.h"
 #include "content/common/content_constants_internal.h"
 #include "content/common/drag_messages.h"
-#include "content/common/view_messages.h"
 #include "content/common/gpu/gpu_messages.h"
+#include "content/common/view_messages.h"
 #include "content/port/browser/render_view_host_delegate_view.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/notification_service.h"
@@ -28,6 +28,7 @@
 #include "content/public/browser/resource_request_details.h"
 #include "content/public/browser/user_metrics.h"
 #include "content/public/browser/web_contents_view.h"
+#include "content/public/common/media_stream_request.h"
 #include "content/public/common/result_codes.h"
 #include "content/browser/browser_plugin/browser_plugin_host_factory.h"
 #include "net/base/net_errors.h"
@@ -45,6 +46,10 @@ namespace content {
 // static
 BrowserPluginHostFactory* BrowserPluginGuest::factory_ = NULL;
 
+namespace {
+const size_t kNumMaxOutstandingMediaRequests = 1024;
+}
+
 BrowserPluginGuest::BrowserPluginGuest(
     int instance_id,
     WebContentsImpl* web_contents,
@@ -62,7 +67,8 @@ BrowserPluginGuest::BrowserPluginGuest(
       name_(params.name),
       auto_size_enabled_(params.auto_size_params.enable),
       max_auto_size_(params.auto_size_params.max_size),
-      min_auto_size_(params.auto_size_params.min_size) {
+      min_auto_size_(params.auto_size_params.min_size),
+      current_media_access_request_id_(0) {
   DCHECK(web_contents);
 }
 
@@ -70,6 +76,7 @@ bool BrowserPluginGuest::OnMessageReceivedFromEmbedder(
     const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(BrowserPluginGuest, message)
+    IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_AllowPermission, OnAllowPermission)
     IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_BuffersSwappedACK,
                         OnSwapBuffersACK)
     IPC_MESSAGE_HANDLER(BrowserPluginHostMsg_DragStatusUpdate,
@@ -580,6 +587,34 @@ void BrowserPluginGuest::AcknowledgeBufferPresent(
                                                  ack_params);
 }
 
+void BrowserPluginGuest::OnAllowPermission(int /*instance_id*/,
+                                           const std::string& permission_type,
+                                           int request_id,
+                                           bool should_allow) {
+  if (permission_type != "media")
+    return;
+
+  MediaStreamRequestsMap::iterator media_request_iter =
+      media_requests_map_.find(request_id);
+  if (media_request_iter == media_requests_map_.end()) {
+    LOG(INFO) << "Not a valid request ID.";
+    return;
+  }
+  const content::MediaStreamRequest& request = media_request_iter->second.first;
+  const content::MediaResponseCallback& callback =
+      media_request_iter->second.second;
+
+  if (should_allow && embedder_web_contents_) {
+    // Re-route the request to the embedder's WebContents; the guest gets the
+    // permission this way.
+    embedder_web_contents_->RequestMediaAccessPermission(request, callback);
+  } else {
+    // Deny the request.
+    callback.Run(content::MediaStreamDevices());
+  }
+  media_requests_map_.erase(media_request_iter);
+}
+
 void BrowserPluginGuest::OnSwapBuffersACK(int instance_id,
                                           int route_id,
                                           int gpu_host_id,
@@ -705,6 +740,29 @@ void BrowserPluginGuest::OnUpdateFrameName(int frame_id,
       name));
 }
 
+void BrowserPluginGuest::RequestMediaAccessPermission(
+    WebContents* web_contents,
+    const content::MediaStreamRequest& request,
+    const content::MediaResponseCallback& callback) {
+  if (media_requests_map_.size() >= kNumMaxOutstandingMediaRequests) {
+    // Deny the media request.
+    // TODO(lazyboy): We should use timeouts to clear these pending requests if
+    // decision has not been made.

[Charlie Reis, 2013/02/13 01:44:47]

I thought we were watching for when event.request was garbage collected.  Is
there a need for a timer?

[lazyboy, 2013/02/13 04:07:48]

yes (Fady also had the same comment), this should not be required anymore,
removed.

+    callback.Run(content::MediaStreamDevices());
+    return;
+  }
+  int request_id = current_media_access_request_id_++;
+  media_requests_map_.insert(
+      std::make_pair(request_id,
+                     std::make_pair(request, callback)));
+
+  base::DictionaryValue request_info;
+  request_info.Set(
+      "url", base::Value::CreateStringValue(request.security_origin.spec()));
+  SendMessageToEmbedder(new BrowserPluginMsg_RequestPermission(
+      embedder_routing_id(), instance_id(), "media", request_id, request_info));
+}
+
 void BrowserPluginGuest::OnUpdateRect(
     const ViewHostMsg_UpdateRect_Params& params) {