Add VideoCaptureImpl

content/renderer/video_capture_message_filter.h

Index: content/renderer/video_capture_message_filter.h
===================================================================
--- content/renderer/video_capture_message_filter.h	(revision 85463)
+++ content/renderer/video_capture_message_filter.h	(working copy)
@@ -34,6 +34,10 @@
     virtual void OnDeviceInfoReceived(
         const media::VideoCaptureParams& device_info) = 0;
 
+    // Called when the delegate has been added to filter's delegate list.
+    // |device_id| is the device id for the delegate.
+    virtual void OnDelegateAdded(int32 device_id) = 0;
+
    protected:
     virtual ~Delegate() {}
   };
@@ -41,14 +45,14 @@
   explicit VideoCaptureMessageFilter(int32 route_id);
   virtual ~VideoCaptureMessageFilter();
 
-  // Add a delegate to the map and return id of the entry.
-  int32 AddDelegate(Delegate* delegate);
+  // Add a delegate to the map.
+  void AddDelegate(Delegate* delegate);
 
   // Remove a delegate from the map.
   void RemoveDelegate(Delegate* delegate);
 
   // Send a message asynchronously.
-  bool Send(IPC::Message* message);
+  virtual bool Send(IPC::Message* message);
 
   void AddFilter();
 
@@ -79,6 +83,7 @@
 
   // A map of device ids to delegates.
   Delegates delegates_;
+  Delegates pending_delegates_;
   int32 last_device_id_;
 
   int32 route_id_;