services/ui: Detect when a video is playing

services/ui/ws/server_window_surface.h

Index: services/ui/ws/server_window_surface.h
diff --git a/services/ui/ws/server_window_surface.h b/services/ui/ws/server_window_surface.h
index 5f1e6d675d51c2c1feda64e292dae3254b3ccead..c5922b3f955a6887e2fa42db7e0bf09262607759 100644
--- a/services/ui/ws/server_window_surface.h
+++ b/services/ui/ws/server_window_surface.h
@@ -41,6 +41,8 @@ class ServerWindowSurface : public mojom::Surface,
     return last_submitted_frame_size_;
   }
 
+  bool may_contain_video() const { return may_contain_video_; }
+
   // mojom::Surface:
   void SubmitCompositorFrame(
       cc::CompositorFrame frame,
@@ -72,6 +74,8 @@ class ServerWindowSurface : public mojom::Surface,
   // Set of surface ids that need to be destroyed.
   std::set<cc::SurfaceId> surfaces_scheduled_for_destruction_;
 
+  bool may_contain_video_ = false;
+
   DISALLOW_COPY_AND_ASSIGN(ServerWindowSurface);
 };