[Chromoting] Re-enable a unit test.

remoting/base/decoder_vp8_unittest.cc

 // Copyright (c) 2012 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.
 
 #include "media/base/video_frame.h"
 #include "remoting/base/codec_test.h"
 #include "remoting/base/decoder_vp8.h"
 #include "remoting/base/encoder_vp8.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 38 matching lines @@
 }
 
 TEST_F(DecoderVp8Test, GradientScaleUpOddToOdd) {
   TestGradient(321, 241, 641, 481, 0.04, 0.02);
 }
 
 TEST_F(DecoderVp8Test, GradientScaleDownEvenToEven) {
   TestGradient(320, 240, 160, 120, 0.04, 0.02);
 }
 
-// TODO(simonmorris): win_tsan and mac_valgrind catch leaks in this test.
-// The maximum error is non-deterministic. The mean error is not too high,
-// which suggests that the problem is restricted to a small area of the output
-// image. See crbug.com/139437.
-TEST_F(DecoderVp8Test, DISABLED_GradientScaleDownEvenToOdd) {
+TEST_F(DecoderVp8Test, GradientScaleDownEvenToOdd) {
+  // The maximum error is non-deterministic. The mean error is not too high,
+  // which suggests that the problem is restricted to a small area of the output
+  // image. See crbug.com/139437 and crbug.com/139633.
   TestGradient(320, 240, 161, 121, 1.0, 0.02);
 }
 
 TEST_F(DecoderVp8Test, GradientScaleDownOddToEven) {
   TestGradient(321, 241, 160, 120, 0.04, 0.02);
 }
 
 TEST_F(DecoderVp8Test, GradientScaleDownOddToOdd) {
   TestGradient(321, 241, 161, 121, 0.04, 0.02);
 }
 
 }  // namespace remoting