media/gpu VDA unittest: Check the number of decoded frames in NotifyFlushDone()

The number of decoded frames should be equal to the number of frames of input
video, if no Reset() is invoked before Flush().
Should check this condition in VDA unittest.

BUG=chromium:834170
TEST=VDA unittest on eve and kevin
TEST=VDA unittest on non-Chrome OS platforms in CQ.

Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: I2eda613522b9a1e6259a9d72c4f86b616bc90996
Reviewed-on: https://chromium-review.googlesource.com/1063910
Commit-Queue: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Pawel Osciak <posciak@chromium.org>
Cr-Commit-Position: refs/heads/master@{#566703}

media/gpu/video_decode_accelerator_unittest.cc

@@ -260,6 +260,8 @@ class GLRenderingVDAClient
   // If |decode_calls_per_second| > 0, |num_in_flight_decodes| must be 1.
   // |render_as_thumbnails| indicates if the decoded picture will be rendered
   // as thumbnails at the end of tests.
+  // |num_frames| is the number of frames that must be verified to be decoded
+  // during the test.
   struct Config {
     size_t window_id = 0;
     size_t num_in_flight_decodes = 1;
@@ -276,6 +278,7 @@ class GLRenderingVDAClient
     size_t delay_reuse_after_frame_num = std::numeric_limits<size_t>::max();
     size_t decode_calls_per_second = 0;
     bool render_as_thumbnails = false;
+    size_t num_frames = 0;
   };
 
   // Doesn't take ownership of |rendering_helper| or |note|, which must outlive
@@ -687,6 +690,11 @@ void GLRenderingVDAClient::NotifyFlushDone() {
     return;
   }
 
+  // Check all the Decode()-ed frames are returned by PictureReady() in
+  // END_OF_STREAM_RESET case.
+  if (config_.reset_point == END_OF_STREAM_RESET)
+    EXPECT_EQ(num_decoded_frames_, config_.num_frames);
+
   SetState(CS_FLUSHED);
   ResetDecoderAfterFlush();
 }
@@ -702,6 +710,8 @@ void GLRenderingVDAClient::NotifyResetDone() {
       DecodeNextFragment();
       return;
     case START_OF_STREAM_RESET:
+      EXPECT_EQ(num_decoded_frames_, 0u);
+      EXPECT_EQ(encoded_data_helper_->AtHeadOfStream(), true);
       reset_point_ = END_OF_STREAM_RESET;
       for (size_t i = 0; i < config_.num_in_flight_decodes; ++i)
         DecodeNextFragment();
@@ -757,6 +767,8 @@ void GLRenderingVDAClient::SetState(ClientState new_state) {
 void GLRenderingVDAClient::FinishInitialization() {
   SetState(CS_INITIALIZED);
   initialize_done_ticks_ = base::TimeTicks::Now();
+  EXPECT_EQ(encoded_data_helper_->AtHeadOfStream(), true);
+  num_decoded_frames_ = 0;
 
   if (reset_point_ == START_OF_STREAM_RESET) {
     decoder_->Reset();
@@ -1160,6 +1172,7 @@ TEST_P(VideoDecodeAcceleratorParamTest, MAYBE_TestSimpleDecode) {
     config.fake_decoder = g_fake_decoder;
     config.delay_reuse_after_frame_num = delay_reuse_after_frame_num;
     config.render_as_thumbnails = render_as_thumbnails;
+    config.num_frames = video_file->num_frames;
 
     clients_[index] = std::make_unique<GLRenderingVDAClient>(
         std::move(config), video_file->data_str, &rendering_helper_,
@@ -1506,6 +1519,7 @@ TEST_F(VideoDecodeAcceleratorTest, TestDecodeTimeMedian) {
   config.profile = video_file->profile;
   config.fake_decoder = g_fake_decoder;
   config.decode_calls_per_second = kWebRtcDecodeCallsPerSecond;
+  config.num_frames = video_file->num_frames;
 
   clients_.push_back(std::make_unique<GLRenderingVDAClient>(
       std::move(config), video_file->data_str, &rendering_helper_,
@@ -1539,6 +1553,7 @@ TEST_F(VideoDecodeAcceleratorTest, NoCrash) {
   config.frame_size = gfx::Size(video_file->width, video_file->height);
   config.profile = video_file->profile;
   config.fake_decoder = g_fake_decoder;
+  config.num_frames = video_file->num_frames;
 
   clients_.push_back(std::make_unique<GLRenderingVDAClient>(
       std::move(config), video_file->data_str, &rendering_helper_,