Start moving WebUserMediaClient on the chromium side to be per frame instead of view.

content/common/frame_messages.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // IPC messages for interacting with frames.
 // Multiply-included message file, hence no include guard.
 
 #include "content/common/content_export.h"
 #include "content/common/content_param_traits.h"
 #include "content/common/frame_message_enums.h"
@@ skipping 559 matching lines @@
                     SkColor /* color */,
                     std::vector<content::ColorSuggestion> /* suggestions */)
 
 // Asks the browser to end the color chooser.
 IPC_MESSAGE_ROUTED1(FrameHostMsg_EndColorChooser, int /* id */)
 
 // Change the selected color in the color chooser.
 IPC_MESSAGE_ROUTED2(FrameHostMsg_SetSelectedColorInColorChooser,
                     int /* id */,
                     SkColor /* color */)
+
+// Notifies the browser that media has started/stopped playing.
+IPC_MESSAGE_ROUTED3(FrameHostMsg_MediaPlayingNotification,
+                    int64 /* player_cookie, distinguishes instances */,
+                    bool /* has_video */,
+                    bool /* has_audio */)
+
+IPC_MESSAGE_ROUTED1(FrameHostMsg_MediaPausedNotification,
+                    int64 /* player_cookie, distinguishes instances */)