[src/media] Declaring the weak_ptr_factory in proper order in cast,mojo and filters

media/cast/test/fake_media_source.h

Index: media/cast/test/fake_media_source.h
diff --git a/media/cast/test/fake_media_source.h b/media/cast/test/fake_media_source.h
index b18d44ea2a8e566751f4e25a2d159a1cad1a7ab6..835fb957943829693f4db63dd208346b49fb8953 100644
--- a/media/cast/test/fake_media_source.h
+++ b/media/cast/test/fake_media_source.h
@@ -112,9 +112,6 @@ class FakeMediaSource {
   int video_frame_count_;
   scoped_ptr<TestAudioBusFactory> audio_bus_factory_;
 
-  // NOTE: Weak pointers must be invalidated before all other member variables.
-  base::WeakPtrFactory<FakeMediaSource> weak_factory_;
-
   base::MemoryMappedFile file_data_;
   scoped_ptr<InMemoryUrlProtocol> protocol_;
   scoped_ptr<FFmpegGlue> glue_;
@@ -143,6 +140,9 @@ class FakeMediaSource {
 
   std::queue<AudioBus*> audio_bus_queue_;
 
+  // NOTE: Weak pointers must be invalidated before all other member variables.
+  base::WeakPtrFactory<FakeMediaSource> weak_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(FakeMediaSource);
 };