Convert plugin and GPU process to brokered handle duplication.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
===================================================================
--- content/renderer/render_thread_impl.cc	(revision 132263)
+++ content/renderer/render_thread_impl.cc	(working copy)
@@ -909,18 +909,15 @@
   // Ask the browser for the channel name.
   int client_id = 0;
   IPC::ChannelHandle channel_handle;
-  base::ProcessHandle renderer_process_for_gpu;
   content::GPUInfo gpu_info;
   if (!Send(new GpuHostMsg_EstablishGpuChannel(cause_for_gpu_launch,
                                                &client_id,
                                                &channel_handle,
-                                               &renderer_process_for_gpu,
                                                &gpu_info)) ||
-      channel_handle.name.empty() ||
 #if defined(OS_POSIX)
       channel_handle.socket.fd == -1 ||
 #endif
-      renderer_process_for_gpu == base::kNullProcessHandle) {
+      channel_handle.name.empty()) {
     // Otherwise cancel the connection.
     gpu_channel_ = NULL;
     return NULL;
@@ -931,7 +928,7 @@
   content::GetContentClient()->SetGpuInfo(gpu_info);
 
   // Connect to the GPU process if a channel name was received.
-  gpu_channel_->Connect(channel_handle, renderer_process_for_gpu);
+  gpu_channel_->Connect(channel_handle);
 
   return GetGpuChannel();
 }