Move MockFFmpeg instance setting into the constructor/destructor.

media/filters/bitstream_converter_unittest.cc

Index: media/filters/bitstream_converter_unittest.cc
===================================================================
--- media/filters/bitstream_converter_unittest.cc	(revision 75179)
+++ media/filters/bitstream_converter_unittest.cc	(working copy)
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -23,9 +23,6 @@
 class BitstreamConverterTest : public testing::Test {
  protected:
   BitstreamConverterTest() {
-    // Initialize MockFFmpeg.
-    MockFFmpeg::set(&mock_ffmpeg_);
-
     memset(&test_stream_context_, 0, sizeof(test_stream_context_));
     memset(&test_filter_, 0, sizeof(test_filter_));
     memset(&test_packet_, 0, sizeof(test_packet_));
@@ -33,10 +30,7 @@
     test_packet_.size = kTestSize1;
   }
 
-  virtual ~BitstreamConverterTest() {
-    // Reset MockFFmpeg.
-    MockFFmpeg::set(NULL);
-  }
+  virtual ~BitstreamConverterTest() {}
 
   AVCodecContext test_stream_context_;
   AVBitStreamFilterContext test_filter_;