Add WARN_UNUSED_RESULT to scoped_refptr::release.

gpu/command_buffer/service/context_group.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 "gpu/command_buffer/service/context_group.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/command_line.h"
@@ skipping 229 matching lines @@
   if (program_manager_ != NULL) {
     program_manager_->Destroy(have_context);
     program_manager_.reset();
   }
 
   if (shader_manager_ != NULL) {
     shader_manager_->Destroy(have_context);
     shader_manager_.reset();
   }
 
-  if (memory_tracker_.get()) {
-    memory_tracker_.release();
-  }
+  memory_tracker_ = NULL;
 }
 
 IdAllocatorInterface* ContextGroup::GetIdAllocator(unsigned namespace_id) {
   if (namespace_id >= arraysize(id_namespaces_))
     return NULL;
 
   return id_namespaces_[namespace_id].get();
 }
 
 uint32 ContextGroup::GetMemRepresented() const {
@@ skipping 41 matching lines @@
     GLenum pname, GLint min_required, uint32* v) {
   uint32 value = 0;
   GetIntegerv(pname, &value);
   bool result = CheckGLFeatureU(min_required, &value);
   *v = value;
   return result;
 }
 
 }  // namespace gles2
 }  // namespace gpu
-
-