Honor --gpu-switching=force_discrete to always stay on discrete GPU.

content/browser/gpu/gpu_process_host.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 "content/browser/gpu/gpu_process_host.h"
 
 #include "base/base_switches.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
@@ skipping 804 matching lines @@
     cmd_line->AppendSwitch(switches::kDisableGpuSandbox);
 
   // Propagate relevant command line switches.
   static const char* const kSwitchNames[] = {
     switches::kDisableBreakpad,
     switches::kDisableGLMultisampling,
     switches::kDisableGpuSandbox,
     switches::kReduceGpuSandbox,
     switches::kDisableSeccompFilterSandbox,
     switches::kEnableGpuSandbox,
-    switches::kDisableGpuSwitching,
     switches::kDisableGpuVsync,
     switches::kDisableGpuWatchdog,
     switches::kDisableImageTransportSurface,
     switches::kDisableAcceleratedVideoDecode,
     switches::kDisableLogging,
     switches::kEnableGPUServiceLogging,
     switches::kEnableLogging,
 #if defined(OS_MACOSX)
     switches::kEnableSandboxLogging,
 #endif
@@ skipping 69 matching lines @@
     const IPC::ChannelHandle& channel_handle,
     base::ProcessHandle renderer_process_for_gpu,
     const content::GPUInfo& gpu_info) {
   callback.Run(channel_handle, gpu_info);
 }
 
 void GpuProcessHost::CreateCommandBufferError(
     const CreateCommandBufferCallback& callback, int32 route_id) {
   callback.Run(route_id);
 }