Use ffmpeg for opus decoding, no need to maintain our decoder.

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 24895905b07e2ec73d04a1e7d642b297571770cd..1c9b6874e60da6de237b4b6ee9c3afa6deb6ace0 100644
--- a/media/test/pipeline_integration_test.cc
+++ b/media/test/pipeline_integration_test.cc
@@ -1575,7 +1575,7 @@ TEST_F(PipelineIntegrationTest, MediaSource_ADTS_TimestampOffset) {
   EXPECT_EQ(592, pipeline_->GetBufferedTimeRanges().end(0).InMilliseconds());
 
   // Verify preroll is stripped.
-  EXPECT_HASH_EQ("-0.06,0.97,-0.90,-0.70,-0.53,-0.34,", GetAudioHash());
+  EXPECT_HASH_EQ("-0.25,0.67,0.04,0.14,-0.49,-0.41,", GetAudioHash());

[wolenetz, 2016/10/21 22:30:58]

Why did this change? Is this related to Opus at all or just an opportunistic fix
here?

 }
 
 TEST_F(PipelineIntegrationTest, BasicPlaybackHashed_MP3) {