Add missing null check on |data_source_|

media/blink/webmediaplayer_impl.cc

 // Copyright 2013 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 <algorithm>
 #include <cmath>
 #include <limits>
 #include <string>
@@ skipping 868 matching lines @@
   }
 #endif
 
   memory_usage_reporting_timer_.Stop();
   ReportMemoryUsage();
 
   // If we're not in an aggressive buffering state, tell the data source we have
   // enough data so that it may release the connection.
   if (buffering_strategy_ !=
       BufferedDataSource::BUFFERING_STRATEGY_AGGRESSIVE) {
-    data_source_->OnBufferingHaveEnough(true);
+    if (data_source_)
+      data_source_->OnBufferingHaveEnough(true);
   }
 
   if (pending_suspend_resume_cycle_) {
     pending_suspend_resume_cycle_ = false;
     pipeline_controller_.Resume();
     return;
   }
 }
 
 void WebMediaPlayerImpl::OnPipelineResumed() {
@@ skipping 583 matching lines @@
 bool WebMediaPlayerImpl::IsAutomaticResumeAllowed() {
 #if defined(OS_ANDROID)
   return !hasVideo() || (delegate_ && !delegate_->IsHidden());
 #else
   // On non-Android platforms Resume() is always allowed.
   return true;
 #endif
 }
 
 }  // namespace media