Add AddChildFrameSink() and RemoveChildFrameSink() To WindowAndroidCompositor

ui/android/window_android_compositor.h

Index: ui/android/window_android_compositor.h
diff --git a/ui/android/window_android_compositor.h b/ui/android/window_android_compositor.h
index 7dfa349f1b4f0834eb83d8338b2a21da3d05cf22..12cc1ddbbffc96c196e8d6bcb62f215c5ae666ef 100644
--- a/ui/android/window_android_compositor.h
+++ b/ui/android/window_android_compositor.h
@@ -30,6 +30,8 @@ class UI_ANDROID_EXPORT WindowAndroidCompositor {
   virtual void SetNeedsAnimate() = 0;
   virtual ResourceManager& GetResourceManager() = 0;
   virtual cc::FrameSinkId GetFrameSinkId() = 0;
+  virtual void AddChildFrameSink(const cc::FrameSinkId& frame_sink_id) = 0;
+  virtual void RemoveChildFrameSink(const cc::FrameSinkId& frame_sink_id) = 0;
 };
 
 }  // namespace ui