Rename VideoDecoder::HasOutputFrameAvailable() to CanReadWithoutStalling().

Also fix the implementation in GpuVideoDecoder to better reflect what we are
checking.

BUG=256899,141788
TEST=Tested on Windows.
R=acolwell@chromium.org, scherkus@chromium.org

Review URL: https://codereview.chromium.org/18580008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@210066 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 25 insertions, 9 deletions

diff --git a/media/base/video_decoder.cc b/media/base/video_decoder.cc
index ba47bae..81397b7 100644
--- a/media/base/video_decoder.cc
+++ b/media/base/video_decoder.cc
@@ -18,7 +18,7 @@ bool VideoDecoder::NeedsBitstreamConversion() const {
   return false;
 }
 
-bool VideoDecoder::HasOutputFrameAvailable() const {
+bool VideoDecoder::CanReadWithoutStalling() const {
   return true;
 }
 
diff --git a/media/base/video_decoder.h b/media/base/video_decoder.h
index 6a4f66a..11d8a7f 100644
--- a/media/base/video_decoder.h
+++ b/media/base/video_decoder.h
@@ -88,7 +88,7 @@ class MEDIA_EXPORT VideoDecoder {
   // a VideoFrame. Most implementations can allocate a new VideoFrame and hence
   // this will always return true. Override and return false for decoders that
   // use a fixed set of VideoFrames for decoding.
-  virtual bool HasOutputFrameAvailable() const;
+  virtual bool CanReadWithoutStalling() const;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(VideoDecoder);
diff --git a/media/filters/gpu_video_decoder.cc b/media/filters/gpu_video_decoder.cc
index 3679a5a..8cf51ad 100644
--- a/media/filters/gpu_video_decoder.cc
+++ b/media/filters/gpu_video_decoder.cc
@@ -480,9 +480,9 @@ bool GpuVideoDecoder::NeedsBitstreamConversion() const {
   return needs_bitstream_conversion_;
 }
 
-bool GpuVideoDecoder::HasOutputFrameAvailable() const {
+bool GpuVideoDecoder::CanReadWithoutStalling() const {
   DCHECK(gvd_loop_proxy_->BelongsToCurrentThread());
-  return available_pictures_ > 0;
+  return available_pictures_ > 0 || !ready_video_frames_.empty();
 }
 
 void GpuVideoDecoder::NotifyInitializeDone() {
diff --git a/media/filters/gpu_video_decoder.h b/media/filters/gpu_video_decoder.h
index 6fd0a3a..225e19d 100644
--- a/media/filters/gpu_video_decoder.h
+++ b/media/filters/gpu_video_decoder.h
@@ -90,7 +90,7 @@ class MEDIA_EXPORT GpuVideoDecoder
   virtual void Stop(const base::Closure& closure) OVERRIDE;
   virtual bool HasAlpha() const OVERRIDE;
   virtual bool NeedsBitstreamConversion() const OVERRIDE;
-  virtual bool HasOutputFrameAvailable() const OVERRIDE;
+  virtual bool CanReadWithoutStalling() const OVERRIDE;
 
   // VideoDecodeAccelerator::Client implementation.
   virtual void NotifyInitializeDone() OVERRIDE;
diff --git a/media/filters/video_frame_stream.cc b/media/filters/video_frame_stream.cc
index 3cf2f37..28aaac6 100644
--- a/media/filters/video_frame_stream.cc
+++ b/media/filters/video_frame_stream.cc
@@ -141,9 +141,9 @@ void VideoFrameStream::Stop(const base::Closure& closure) {
   message_loop_->PostTask(FROM_HERE, base::ResetAndReturn(&stop_cb_));
 }
 
-bool VideoFrameStream::HasOutputFrameAvailable() const {
+bool VideoFrameStream::CanReadWithoutStalling() const {
   DCHECK(message_loop_->BelongsToCurrentThread());
-  return decoder_->HasOutputFrameAvailable();
+  return decoder_->CanReadWithoutStalling();
 }
 
 void VideoFrameStream::Read(const DemuxerStream::ReadCB& demuxer_read_cb) {
diff --git a/media/filters/video_frame_stream.h b/media/filters/video_frame_stream.h
index e560557..c384bca 100644
--- a/media/filters/video_frame_stream.h
+++ b/media/filters/video_frame_stream.h
@@ -68,7 +68,7 @@ class MEDIA_EXPORT VideoFrameStream : public DemuxerStream {
 
   // Returns true if the decoder currently has the ability to decode and return
   // a VideoFrame.
-  bool HasOutputFrameAvailable() const;
+  bool CanReadWithoutStalling() const;
 
   // DemuxerStream implementation.
   virtual void Read(const ReadCB& read_cb) OVERRIDE;
diff --git a/media/filters/video_renderer_base.cc b/media/filters/video_renderer_base.cc
index a39c8b0..5c6c168 100644
--- a/media/filters/video_renderer_base.cc
+++ b/media/filters/video_renderer_base.cc
@@ -396,7 +396,7 @@ void VideoRendererBase::FrameReady(VideoDecoder::Status status,
   AddReadyFrame_Locked(frame);
 
   if (state_ == kPrerolling) {
-    if (!video_frame_stream_.HasOutputFrameAvailable() ||
+    if (!video_frame_stream_.CanReadWithoutStalling() ||
         ready_frames_.size() >= static_cast<size_t>(limits::kMaxVideoFrames)) {
       TransitionToPrerolled_Locked();
     }
diff --git a/media/filters/video_renderer_base_unittest.cc b/media/filters/video_renderer_base_unittest.cc
index 945940a..8044a11 100644
--- a/media/filters/video_renderer_base_unittest.cc
+++ b/media/filters/video_renderer_base_unittest.cc
@@ -507,6 +507,22 @@ TEST_F(VideoRendererBaseTest, Preroll_RightAfter) {
   Shutdown();
 }
 
+TEST_F(VideoRendererBaseTest, PlayAfterPreroll) {
+  Initialize();
+  Pause();
+  Flush();
+  QueuePrerollFrames(kFrameDurationInMs * 4);
+
+  Preroll(kFrameDurationInMs * 4, PIPELINE_OK);
+  EXPECT_EQ(kFrameDurationInMs * 4, GetCurrentTimestampInMs());
+
+  Play();
+  // Advance time past prerolled time to trigger a Read().
+  AdvanceTimeInMs(5 * kFrameDurationInMs);
+  WaitForPendingRead();
+  Shutdown();
+}
+
 TEST_F(VideoRendererBaseTest, GetCurrentFrame_Initialized) {
   Initialize();
   EXPECT_TRUE(GetCurrentFrame().get());  // Due to prerolling.