media/vpx: Add support for VP9 alpha channel

media/test/pipeline_integration_test.cc

Index: media/test/pipeline_integration_test.cc
diff --git a/media/test/pipeline_integration_test.cc b/media/test/pipeline_integration_test.cc
index 0644c361dc7a2d938f99a8247f2faa8443cb96c4..3f82ff5ddaf78281d6614c4502aa7faafcd80ca5 100644
--- a/media/test/pipeline_integration_test.cc
+++ b/media/test/pipeline_integration_test.cc
@@ -1833,6 +1833,22 @@ TEST_F(PipelineIntegrationTest, BasicPlayback_VP9_Odd_WebM) {
   ASSERT_TRUE(WaitUntilOnEnded());
 }
 
+// Verify that VP9 video with alpha channel can be played back.
+TEST_F(PipelineIntegrationTest, BasicPlayback_VP9A_WebM) {
+  ASSERT_EQ(PIPELINE_OK, Start("bear-vp9a.webm"));

[DaleCurtis, 2016/01/05 21:22:21]

Can you  create these as kClockless type tests? We're starting to get too many
of these and they take #media_duration in real-time to complete.

[vignesh, 2016/01/06 00:07:49]

I have marked these two as kClockless. Would you like me to change the other
BasicPlayback_VP{8,9}_* tests as well?

[DaleCurtis, 2016/01/06 00:16:48]

Sure, if they all still pass.

+  Play();
+  ASSERT_TRUE(WaitUntilOnEnded());
+  EXPECT_VIDEO_FORMAT_EQ(last_video_frame_format_, PIXEL_FORMAT_YV12A);
+}
+
+// Verify that VP9A video with odd width/height can be played back.
+TEST_F(PipelineIntegrationTest, BasicPlayback_VP9A_Odd_WebM) {
+  ASSERT_EQ(PIPELINE_OK, Start("bear-vp9a-odd-dimensions.webm"));
+  Play();
+  ASSERT_TRUE(WaitUntilOnEnded());
+  EXPECT_VIDEO_FORMAT_EQ(last_video_frame_format_, PIXEL_FORMAT_YV12A);
+}
+
 #if !defined(DISABLE_TEXT_TRACK_TESTS)
 // Verify that VP8 video with inband text track can be played back.
 TEST_F(PipelineIntegrationTest, BasicPlayback_VP8_WebVTT_WebM) {