Monitor the intersection of video and viewport.

third_party/WebKit/public/platform/WebMediaPlayer.h

Index: third_party/WebKit/public/platform/WebMediaPlayer.h
diff --git a/third_party/WebKit/public/platform/WebMediaPlayer.h b/third_party/WebKit/public/platform/WebMediaPlayer.h
index 87c058c8da7cf3760c0fa3293db6c6c03b65dd3d..0a96fee5f91bed1373244e73caa89697e5d8b713 100644
--- a/third_party/WebKit/public/platform/WebMediaPlayer.h
+++ b/third_party/WebKit/public/platform/WebMediaPlayer.h
@@ -35,6 +35,7 @@
 #include "WebCanvas.h"
 #include "WebContentDecryptionModule.h"
 #include "WebMediaSource.h"
+#include "WebRect.h"
 #include "WebSetSinkIdCallbacks.h"
 #include "WebString.h"
 
@@ -54,7 +55,6 @@ class WebMediaPlayerSource;
 class WebSecurityOrigin;
 class WebString;
 class WebURL;
-struct WebRect;
 struct WebSize;
 
 class WebMediaPlayer {
@@ -105,6 +105,15 @@ class WebMediaPlayer {
   typedef WebString TrackId;
   enum TrackType { TextTrack, AudioTrack, VideoTrack };
 
+  struct ViewportIntersectionInfo {
+    ViewportIntersectionInfo() {}
+    ~ViewportIntersectionInfo() {}
+
+    float ratio = 0;

[miu, 2016/11/15 23:29:26]

Please remove |ratio|. This can be computed in remoting_controller.cc where it
is needed. (This is what we were talking about earlier today, face-to-face.)

For all other cases, where you use ratio > 0.0f to determine visibility, just
use !intersectRect.empty() instead.

[xjz, 2016/11/16 01:06:45]

Done.

+    WebRect rootRect;
+    WebRect intersectRect;
+  };
+
   virtual ~WebMediaPlayer() {}
 
   virtual void load(LoadType, const WebMediaPlayerSource&, CORSMode) = 0;
@@ -226,6 +235,10 @@ class WebMediaPlayer {
   // Inform WebMediaPlayer when the element has entered/exited fullscreen.
   virtual void enteredFullscreen() {}
   virtual void exitedFullscreen() {}
+  // Inform WebMediaPlayer when the intersection rect of video and viewport
+  // changes.
+  virtual void videoViewportIntersectionChanged(
+      const ViewportIntersectionInfo& info) {}
 
   virtual void enabledAudioTracksChanged(
       const WebVector<TrackId>& enabledTrackIds) {}