Refactor media out of WebContentsImpl to MediaWebContentsObserver.

chrome/browser/engagement/site_engagement_helper_unittest.cc

 // Copyright 2015 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 "base/command_line.h"
 #include "base/test/histogram_tester.h"
 #include "base/timer/mock_timer.h"
 #include "base/values.h"
 #include "chrome/browser/engagement/site_engagement_helper.h"
 #include "chrome/browser/engagement/site_engagement_service.h"
@@ skipping 35 matching lines @@
                                          blink::WebInputEvent::Type type) {
     helper->input_tracker_.DidGetUserInteraction(type);
     helper->input_tracker_.TrackingStarted();
   }
 
   void HandleMediaPlaying(SiteEngagementHelper* helper, bool is_hidden) {
     helper->RecordMediaPlaying(is_hidden);
   }
 
   void MediaStartedPlaying(SiteEngagementHelper* helper) {
-    helper->media_tracker_.MediaStartedPlaying();
+    helper->media_tracker_.MediaStartedPlaying(
+        content::WebContentsObserver::MediaPlayerId(nullptr, 1));
   }
 
   void MediaPaused(SiteEngagementHelper* helper) {
-    helper->media_tracker_.MediaPaused();
+    helper->media_tracker_.MediaPaused(
+        content::WebContentsObserver::MediaPlayerId(nullptr, 1));
   }
 
   // Set a pause timer on the input tracker for test purposes.
   void SetInputTrackerPauseTimer(SiteEngagementHelper* helper,
                                  scoped_ptr<base::Timer> timer) {
     helper->input_tracker_.SetPauseTimerForTesting(timer.Pass());
   }
 
   // Set a pause timer on the input tracker for test purposes.
   void SetMediaTrackerPauseTimer(SiteEngagementHelper* helper,
@@ skipping 501 matching lines @@
   // When the timer fires, callbacks are added.
   input_tracker_timer->Fire();
   EXPECT_FALSE(input_tracker_timer->IsRunning());
   EXPECT_TRUE(IsTrackingInput(helper.get()));
 
   // Navigation should start the initial delay timer again.
   NavigateWithDisposition(url1, CURRENT_TAB);
   EXPECT_TRUE(input_tracker_timer->IsRunning());
   EXPECT_FALSE(IsTrackingInput(helper.get()));
 }