Detect change on the intersection of video and viewport.

third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp

Index: third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp
diff --git a/third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp b/third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp
index 2081e50930d46df5178f439c030e0c500b6519f8..bb33de761741567739348b9cdde36befc8de1469 100644
--- a/third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp
+++ b/third_party/WebKit/Source/web/FrameLoaderClientImpl.cpp
@@ -775,9 +775,15 @@ std::unique_ptr<WebMediaPlayer> FrameLoaderClientImpl::createWebMediaPlayer(
   HTMLMediaElementEncryptedMedia& encryptedMedia =
       HTMLMediaElementEncryptedMedia::from(htmlMediaElement);
   WebString sinkId(HTMLMediaElementAudioOutputDevice::sinkId(htmlMediaElement));
-  return wrapUnique(webFrame->client()->createMediaPlayer(
-      source, client, &encryptedMedia, encryptedMedia.contentDecryptionModule(),
-      sinkId));
+
+  std::unique_ptr<WebMediaPlayer> mediaPlayer =
+      wrapUnique(webFrame->client()->createMediaPlayer(
+          source, client, &encryptedMedia,
+          encryptedMedia.contentDecryptionModule(), sinkId));
+  WebMediaPlayer::ViewportIntersectionInfo intersectInfo =

[miu, 2016/11/22 00:14:30]

nit: Is this local variable (intersectInfo) needed? You can eliminate a copy of
the struct by:

  mediaPlayer->viewportIntersectionChanged(
      htmlMediaElement.currentViewportIntersection());

[xjz, 2016/11/23 23:43:25]

Not applicable. I find that we don't need make change here. Instead, this can be
done in HTMLMediaElement.

+      htmlMediaElement.currentViewportIntersection();
+  mediaPlayer->viewportIntersectionChanged(intersectInfo);
+  return mediaPlayer;
 }
 
 WebRemotePlaybackClient* FrameLoaderClientImpl::createWebRemotePlaybackClient(