Fix media timeline so that thumb never exceeds buffered data

media/filters/video_renderer_base.cc

Index: media/filters/video_renderer_base.cc
diff --git a/media/filters/video_renderer_base.cc b/media/filters/video_renderer_base.cc
index 02022698cc1b34b1886c185818cf660ea06cec76..b35d1e0de3b48eed234011540697f6188c9f10ec 100644
--- a/media/filters/video_renderer_base.cc
+++ b/media/filters/video_renderer_base.cc
@@ -63,6 +63,8 @@ void VideoRendererBase::Stop(const base::Closure& callback) {
     base::AutoLock auto_lock(lock_);
     state_ = kStopped;
 
+    statistics_callback_.Reset();
+    video_time_cb_.Reset();
     if (!pending_paint_ && !pending_paint_with_last_available_)
       DoStopOrError_Locked();
 
@@ -99,16 +101,19 @@ void VideoRendererBase::Seek(base::TimeDelta time, const FilterStatusCB& cb) {
 }
 
 void VideoRendererBase::Initialize(VideoDecoder* decoder,
-                                   const base::Closure& callback,
-                                   const StatisticsCallback& stats_callback) {
+                                   const base::Closure& init_cb,
+                                   const StatisticsCallback& stats_callback,
+                                   const VideoTimeCB& video_time_cb) {
   base::AutoLock auto_lock(lock_);
   DCHECK(decoder);
-  DCHECK(!callback.is_null());
+  DCHECK(!init_cb.is_null());
   DCHECK(!stats_callback.is_null());
+  DCHECK(!video_time_cb.is_null());
   DCHECK_EQ(kUninitialized, state_);
   decoder_ = decoder;
 
   statistics_callback_ = stats_callback;
+  video_time_cb_ = video_time_cb;
 
   // Notify the pipeline of the video dimensions.
   host()->SetNaturalVideoSize(decoder_->natural_size());
@@ -127,7 +132,7 @@ void VideoRendererBase::Initialize(VideoDecoder* decoder,
     NOTREACHED() << "Video thread creation failed";
     state_ = kError;
     host()->SetError(PIPELINE_ERROR_INITIALIZATION_FAILED);
-    callback.Run();
+    init_cb.Run();
     return;
   }
 
@@ -136,7 +141,7 @@ void VideoRendererBase::Initialize(VideoDecoder* decoder,
   // TODO(scherkus): find out if this is necessary, but it seems to help.
   ::SetThreadPriority(thread_, THREAD_PRIORITY_ABOVE_NORMAL);
 #endif  // defined(OS_WIN)
-  callback.Run();
+  init_cb.Run();
 }
 
 bool VideoRendererBase::HasEnded() {
@@ -369,6 +374,7 @@ void VideoRendererBase::FrameReady(scoped_refptr<VideoFrame> frame) {
   ready_frames_.push_back(frame);
   DCHECK_LE(ready_frames_.size(),
             static_cast<size_t>(limits::kMaxVideoFrames));
+  video_time_cb_.Run(frame->GetTimestamp() + frame->GetDuration());
   frame_available_.Signal();
 
   PipelineStatistics statistics;