media: Add MediaPermission interface and MediaPermissionDispatcher.

content/renderer/render_frame_impl.h

Index: content/renderer/render_frame_impl.h
diff --git a/content/renderer/render_frame_impl.h b/content/renderer/render_frame_impl.h
index e4f2901a32959a0b3d03a73ca3d5e8e76a896f4d..6fd6820c950aeff6d9b0de0c2afe1be93e33c56f 100644
--- a/content/renderer/render_frame_impl.h
+++ b/content/renderer/render_frame_impl.h
@@ -79,6 +79,7 @@ class GeolocationDispatcher;
 class ManifestManager;
 class MediaStreamDispatcher;
 class MediaStreamRendererFactory;
+class MediaPermissionDispatcher;
 class MidiDispatcher;
 class NotificationPermissionDispatcher;
 class PageState;
@@ -816,6 +817,9 @@ class CONTENT_EXPORT RenderFrameImpl
   // EncryptedMediaClient attached to this frame; lazily initialized.
   scoped_ptr<media::WebEncryptedMediaClientImpl> web_encrypted_media_client_;
 
+  // The media permission dispatcher attached to this frame, lazily initialized.
+  MediaPermissionDispatcher* media_permission_dispatcher_;
+
   // MidiClient attached to this frame; lazily initialized.
   MidiDispatcher* midi_dispatcher_;