Enables fullscreen subtitle and media control from Blink

content/browser/renderer_host/render_widget_host_view_android.h

Index: content/browser/renderer_host/render_widget_host_view_android.h
diff --git a/content/browser/renderer_host/render_widget_host_view_android.h b/content/browser/renderer_host/render_widget_host_view_android.h
index 9e46acb1760f0a8c8f65216dee3cf40b08a00bc7..dca113e6892b6875d288496fdd956715f10060a9 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.h
+++ b/content/browser/renderer_host/render_widget_host_view_android.h
@@ -241,6 +241,8 @@ class RenderWidgetHostViewAndroid
   void SynchronousFrameMetadata(
       const cc::CompositorFrameMetadata& frame_metadata);
 
+  void SetOverlayVideoMode(bool enabled);
+
  private:
   void BuffersSwapped(const gpu::Mailbox& mailbox,
                       uint32_t output_surface_id,
@@ -332,6 +334,8 @@ class RenderWidgetHostViewAndroid
 
   bool flush_input_requested_;
 
+  bool overlay_video_mode_;
+
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAndroid);
 };