Remove GPU relinquish resources infrastructure and stop GPU process.

ui/ozone/public/gpu_platform_support.cc

 // Copyright 2014 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 "ui/ozone/public/gpu_platform_support.h"
 
 #include "base/logging.h"
 #include "ui/ozone/ozone_export.h"
 
 namespace ui {
 
 namespace {
 
 // No-op implementation of GpuPlatformSupport.
 class StubGpuPlatformSupport : public GpuPlatformSupport {
  public:
   // GpuPlatformSupport:
   void OnChannelEstablished(IPC::Sender* sender) override {}
   bool OnMessageReceived(const IPC::Message&) override { return false; }
-  void RelinquishGpuResources(const base::Closure& callback) override;
   IPC::MessageFilter* GetMessageFilter() override { return nullptr; }
 };
 
-void StubGpuPlatformSupport::RelinquishGpuResources(
-    const base::Closure& callback) {
-  callback.Run();
-}
-
 }  // namespace
 
 GpuPlatformSupport::GpuPlatformSupport() {
 }
 
 GpuPlatformSupport::~GpuPlatformSupport() {
 }
 
 GpuPlatformSupport* CreateStubGpuPlatformSupport() {
   return new StubGpuPlatformSupport;
 }
 
 }  // namespace ui