Use ChannelMojo for GpuChannels.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index c6efb70325232304bf82841f49a7a7137ea9e23d..c78aec056209f1e3a68698201456a7f8e48c9121 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -1801,10 +1801,7 @@ scoped_refptr<gpu::GpuChannelHost> RenderThreadImpl::EstablishGpuChannelSync(
     // Ask the browser for the channel name.
     if (!Send(new ChildProcessHostMsg_EstablishGpuChannel(
             cause_for_gpu_launch, &client_id, &channel_handle, &gpu_info)) ||
-#if defined(OS_POSIX)
-        channel_handle.socket.fd == -1 ||
-#endif
-        channel_handle.name.empty()) {
+        !channel_handle.mojo_handle.is_valid()) {
       // Otherwise cancel the connection.
       return nullptr;
     }