Create video and audio decoder threads on demand.

media/filters/ffmpeg_audio_decoder_unittest.cc

Index: media/filters/ffmpeg_audio_decoder_unittest.cc
diff --git a/media/filters/ffmpeg_audio_decoder_unittest.cc b/media/filters/ffmpeg_audio_decoder_unittest.cc
index 0c7bed56ede4fb3e3ae84cb1b8e5bf7e81621f76..2c97058c120c13fa996cc2a9abe599ec565e646f 100644
--- a/media/filters/ffmpeg_audio_decoder_unittest.cc
+++ b/media/filters/ffmpeg_audio_decoder_unittest.cc
@@ -13,6 +13,7 @@
 #include "media/base/test_data_util.h"
 #include "media/ffmpeg/ffmpeg_common.h"
 #include "media/filters/ffmpeg_audio_decoder.h"
+#include "media/filters/ffmpeg_decoder_unittest.h"
 #include "media/filters/ffmpeg_glue.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -25,11 +26,12 @@ namespace media {
 ACTION_P(InvokeReadPacket, test) {
   test->ReadPacket(arg0);
 }
-
+
 class FFmpegAudioDecoderTest : public testing::Test {
- public:
+ public:
   FFmpegAudioDecoderTest()
-      : decoder_(new FFmpegAudioDecoder(&message_loop_)),
+      : decoder_(new FFmpegAudioDecoder(base::Bind(&Identity<MessageLoop*>,
+                                                   &message_loop_))),
         demuxer_(new StrictMock<MockDemuxerStream>()) {
     CHECK(FFmpegGlue::GetInstance());