Revert 75444 - Move MockFFmpeg instance setting into the constructor/destruct...

media/filters/ffmpeg_video_decoder_unittest.cc

Index: media/filters/ffmpeg_video_decoder_unittest.cc
===================================================================
--- media/filters/ffmpeg_video_decoder_unittest.cc	(revision 75447)
+++ media/filters/ffmpeg_video_decoder_unittest.cc	(working copy)
@@ -156,6 +156,9 @@
     stream_.r_frame_rate.den = 1;
     buffer_ = new DataBuffer(1);
     end_of_stream_buffer_ = new DataBuffer(0);
+
+    // Initialize MockFFmpeg.
+    MockFFmpeg::set(&mock_ffmpeg_);
   }
 
   virtual ~FFmpegVideoDecoderTest() {
@@ -169,6 +172,9 @@
 
     // Finish up any remaining tasks.
     message_loop_.RunAllPending();
+
+    // Reset MockFFmpeg.
+    MockFFmpeg::set(NULL);
   }
 
   void InitializeDecoderSuccessfully() {