Enable smooth transition when show/hide media remoting interstitial.

third_party/WebKit/Source/core/html/shadow/MediaRemotingInterstitial.h

Index: third_party/WebKit/Source/core/html/shadow/MediaRemotingInterstitial.h
diff --git a/third_party/WebKit/Source/core/html/shadow/MediaRemotingInterstitial.h b/third_party/WebKit/Source/core/html/shadow/MediaRemotingInterstitial.h
index 0baaa2bdd0039f110dfbc97fce57910d4e857837..f68824f815d67db267da9a280686ba5acd6a833f 100644
--- a/third_party/WebKit/Source/core/html/shadow/MediaRemotingInterstitial.h
+++ b/third_party/WebKit/Source/core/html/shadow/MediaRemotingInterstitial.h
@@ -34,6 +34,7 @@ class MediaRemotingInterstitial final : public HTMLDivElement {
   // Show/Hide Media Remoting interstitial.
   void Show();
   void Hide();
+
   void OnPosterImageChanged();
 
   HTMLVideoElement& GetVideoElement() const { return *video_element_; }
@@ -43,7 +44,11 @@ class MediaRemotingInterstitial final : public HTMLDivElement {
  private:
   // Node override.
   bool IsMediaRemotingInterstitial() const override { return true; }
+  void ToggleInterstitialTimerFired(TimerBase*);

[kinuko, 2017/04/19 06:13:43]

If this one's not overrides please don't interleave.

[xjz, 2017/04/19 17:11:20]

Done.

+  void DidMoveToNewDocument(Document&) override;
 
+  bool is_shown_;

[mlamouri (slow - plz ping), 2017/04/19 16:17:19]

nit: initialise the bool here. Also, add a comment explaining what it actually
means. Because we are transitioning, visibility isn't really a boolean so does
it include "transitions" or not?

Maybe it should be named `is_visible_or_transitioning_`?

[xjz, 2017/04/19 17:11:20]

Done. Added comments. This boolean indicates whether we should show the
interstitial. It could be in transition or after.

+  TaskRunnerTimer<MediaRemotingInterstitial> toggle_insterstitial_timer_;
   Member<HTMLVideoElement> video_element_;
   Member<HTMLImageElement> background_image_;
   Member<MediaRemotingExitButtonElement> exit_button_;