Use mus::MojoGpuMemoryBufferManager in mus::GpuService.

components/mus/gpu/gpu_service_impl.cc

Index: components/mus/gpu/gpu_service_impl.cc
diff --git a/components/mus/gpu/gpu_service_impl.cc b/components/mus/gpu/gpu_service_impl.cc
index 339011b605d80bb62eff48c114fa9034f94ee2c2..2b5e328e3b92151b7dcb700a859313da0f0b36d6 100644
--- a/components/mus/gpu/gpu_service_impl.cc
+++ b/components/mus/gpu/gpu_service_impl.cc
@@ -13,8 +13,8 @@ namespace mus {
 namespace {
 
 void EstablishGpuChannelDone(
-    int32_t client_id,
     const mojom::GpuService::EstablishGpuChannelCallback& callback,
+    int32_t client_id,
     const IPC::ChannelHandle& channel_handle) {
   // TODO(penghuang): Send the GPUInfo to the client.
   callback.Run(client_id, mojom::ChannelHandle::From(channel_handle), nullptr);
@@ -24,29 +24,23 @@ void EstablishGpuChannelDone(
 GpuServiceImpl::GpuServiceImpl(
     mojo::InterfaceRequest<mojom::GpuService> request,
     shell::Connection* connection)
-    : binding_(this, std::move(request)),
-      client_id_(connection->GetRemoteInstanceID() + 1) {
-  // Use remote instead id + 1 as client id, so every GpuServiceImpl instances
-  // for a same client will have the same client id.
-  // Make sure client_id_ is greater than 1, because 1 is used for the local
-  // GpuChannel.
-  DCHECK_GT(client_id_, 1);
-}
+    : binding_(this, std::move(request)) {}
 
 GpuServiceImpl::~GpuServiceImpl() {}
 
 void GpuServiceImpl::EstablishGpuChannel(
     const mojom::GpuService::EstablishGpuChannelCallback& callback) {
   GpuServiceMus* service = GpuServiceMus::GetInstance();
+  // TODO(penghuang): figure out how to generate a meaningful tracing id.

[piman, 2016/06/03 21:02:31]

The important part is that the tracing ID given to the GPU process is the same
as the tracing ID used for tracing, or other allocations done on behalf of the
connecting process.
This is so we can correctly attribute memory to the process. This needs to be
thought about more generally in the mus design. Maybe file a bug?

[Peng, 2016/06/06 14:10:33]

Filed a bug. Done

+  const uint64_t client_tracing_id = 0;
   // TODO(penghuang): windows server may want to control those flags.
   // Add a private interface for windows server.
   const bool preempts = false;
   const bool allow_view_command_buffers = false;
   const bool allow_real_time_streams = false;
   service->EstablishGpuChannel(
-      client_id_, client_id_, preempts, allow_view_command_buffers,
-      allow_real_time_streams,
-      base::Bind(&EstablishGpuChannelDone, client_id_, callback));
+      client_tracing_id, preempts, allow_view_command_buffers,
+      allow_real_time_streams, base::Bind(&EstablishGpuChannelDone, callback));
 }
 
 void GpuServiceImpl::CreateGpuMemoryBuffer(