Disable background video track behind a feature flag

media/blink/webmediaplayer_impl_unittest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/blink/webmediaplayer_impl.h"
 
 #include <stdint.h>
 
 #include <memory>
 
@@ skipping 69 matching lines @@
   void removeVideoTrack(blink::WebMediaPlayer::TrackId) override {}
   void addTextTrack(blink::WebInbandTextTrack*) override {}
   void removeTextTrack(blink::WebInbandTextTrack*) override {}
   void mediaSourceOpened(blink::WebMediaSource*) override {}
   void requestSeek(double) override {}
   void remoteRouteAvailabilityChanged(bool) override {}
   void connectedToRemoteDevice() override {}
   void disconnectedFromRemoteDevice() override {}
   void cancelledRemotePlaybackRequest() override {}
   void remotePlaybackStarted() override {}
+  void hidden() override {}
+  void shown() override {}
   bool isAutoplayingMuted() override { return is_autoplaying_muted_; }
   void requestReload(const blink::WebURL& newUrl) override {}
 
   void set_is_autoplaying_muted(bool value) { is_autoplaying_muted_ = value; }
 
  private:
   bool is_autoplaying_muted_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(DummyWebMediaPlayerClient);
 };
@@ skipping 617 matching lines @@
   EXPECT_CALL(delegate_, DidPlay(_, true, false, false, _));
   client_.set_is_autoplaying_muted(true);
   SetDelegateState(WebMediaPlayerImpl::DelegateState::PLAYING);
 
   EXPECT_CALL(delegate_, DidPlay(_, true, true, false, _));
   client_.set_is_autoplaying_muted(false);
   wmpi_->setVolume(1.0);
 }
 
 }  // namespace media