gpu: Fix some context lost marking glitches+leaks and add UMA stats

gpu/command_buffer/service/gl_context_mock.cc

Index: gpu/command_buffer/service/gl_context_mock.cc
diff --git a/media/base/media_permission.cc b/gpu/command_buffer/service/gl_context_mock.cc
similarity index 52%
copy from media/base/media_permission.cc
copy to gpu/command_buffer/service/gl_context_mock.cc
index 739e4454ae76be702c1ddde201fc9680575d9c9e..ce5d10f2770c95c59d0ad70129594dc474359256 100644
--- a/media/base/media_permission.cc
+++ b/gpu/command_buffer/service/gl_context_mock.cc
@@ -2,14 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "media/base/media_permission.h"
+#include "gpu/command_buffer/service/gl_context_mock.h"
 
-namespace media {
+namespace gpu {
 
-MediaPermission::MediaPermission() {
+GLContextMock::GLContextMock() {
 }
-
-MediaPermission::~MediaPermission() {
+GLContextMock::~GLContextMock() {
 }
 
-}  // namespace media
+}  // namespace gpu