Cleanup GpuMemoryManager and helpers.

ui/gl/gl_context.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 <string>
 
 #include "base/bind.h"
 #include "base/cancelable_callback.h"
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
@@ skipping 48 matching lines @@
   share_group_->AddContext(this);
 }
 
 GLContext::~GLContext() {
   share_group_->RemoveContext(this);
   if (GetCurrent() == this) {
     SetCurrent(nullptr);
   }
 }
 
-bool GLContext::GetTotalGpuMemory(size_t* bytes) {
-  DCHECK(bytes);
-  *bytes = 0;
-  return false;
-}
-
 void GLContext::SetSafeToForceGpuSwitch() {
 }
 
 bool GLContext::ForceGpuSwitchIfNeeded() {
   return true;
 }
 
 void GLContext::SetUnbindFboOnMakeCurrent() {
   NOTIMPLEMENTED();
 }
@@ skipping 162 matching lines @@
 }
 
 GLContextReal::~GLContextReal() {}
 
 void GLContextReal::SetCurrent(GLSurface* surface) {
   GLContext::SetCurrent(surface);
   current_real_context_.Pointer()->Set(surface ? this : nullptr);
 }
 
 }  // namespace gfx