Use enum instead of string in MessageLoopFactory::GetMessageLoop*

media/filters/ffmpeg_video_decoder_unittest.cc

Index: media/filters/ffmpeg_video_decoder_unittest.cc
diff --git a/media/filters/ffmpeg_video_decoder_unittest.cc b/media/filters/ffmpeg_video_decoder_unittest.cc
index 11c9a08df0966e9feaacb8b5fa6bdef0d56db781..be32dac8d8c92589d8ba47aa3679e6bf119ee155 100644
--- a/media/filters/ffmpeg_video_decoder_unittest.cc
+++ b/media/filters/ffmpeg_video_decoder_unittest.cc
@@ -77,9 +77,10 @@ class FFmpegVideoDecoderTest : public testing::Test {
                             base::Unretained(this))) {
     CHECK(FFmpegGlue::GetInstance());
 
-    decoder_ = new FFmpegVideoDecoder(base::Bind(&Identity<MessageLoop*>,
-                                                 &message_loop_),
-                                      decryptor_.get());
+    decoder_ = new FFmpegVideoDecoder(
+        base::Bind(&Identity<scoped_refptr<base::MessageLoopProxy> >,
+                   message_loop_.message_loop_proxy()),
+        decryptor_.get());
 
     // Initialize various test buffers.
     frame_buffer_.reset(new uint8[kCodedSize.GetArea()]);