Make lost context and error message callbacks on GpuControl go to client

components/mus/gles2/command_buffer_local.cc

 // Copyright 2015 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 "components/mus/gles2/command_buffer_local.h"
 
 #include "base/atomic_sequence_num.h"
 #include "base/bind.h"
 #include "base/memory/shared_memory.h"
 #include "base/synchronization/waitable_event.h"
@@ skipping 173 matching lines @@
     int32_t* id) {
   DCHECK(CalledOnValidThread());
   if (size >= std::numeric_limits<uint32_t>::max())
     return nullptr;
 
   void* memory = nullptr;
   mojo::ScopedSharedBufferHandle handle;
   mojo::ScopedSharedBufferHandle duped;
   if (!CreateMapAndDupSharedBuffer(size, &memory, &handle, &duped)) {
     if (last_state_.error == gpu::error::kNoError)
       last_state_.error = gpu::error::kLostContext;

[danakj, 2016/04/07 20:26:38]

I mean, this never had callbacks before, but maybe this should actually call the
client here?

     return nullptr;
   }
 
   *id = ++next_transfer_buffer_id_;
 
   gpu_state_->command_buffer_task_runner()->PostTask(
       driver_.get(),
       base::Bind(&CommandBufferLocal::RegisterTransferBufferOnGpuThread,
                  base::Unretained(this), *id, base::Passed(&duped),
                  static_cast<uint32_t>(size)));
   scoped_ptr<gpu::BufferBacking> backing(
       new mus::MojoBufferBacking(std::move(handle), memory, size));
   scoped_refptr<gpu::Buffer> buffer(new gpu::Buffer(std::move(backing)));
   return buffer;
 }
 
 void CommandBufferLocal::DestroyTransferBuffer(int32_t id) {
   DCHECK(CalledOnValidThread());
   gpu_state_->command_buffer_task_runner()->PostTask(
       driver_.get(),
       base::Bind(&CommandBufferLocal::DestroyTransferBufferOnGpuThread,
                  base::Unretained(this), id));
 }
 
+void CommandBufferLocal::SetGpuControlClient(gpu::GpuControlClient*) {
+  // This implementation of GpuControl has no concept of losing the context
+  // (see IsGpuChannelLost), and no error messages, so we don't bother storing
+  // the client.

[no sievers, 2016/04/07 21:07:58]

It does handle lost contexts and trigger the callback to the client though. It's
just that it's forwarded from CommandBufferDriver to
CommandBufferLocal::DidLoseContext() separately.

I guess this class is something like GLInProcessContext/InProcessCommandBuffer
which blurs the notion of client/service a bit.

[danakj, 2016/04/07 21:45:18]

Ooops thanks, I was looking for "Lost" not "Lose".

So the SurfacesContextProvider should just pass the lost context callback given
to it thru to the GLES2Impl, and this will call the GLES2Impl on loss.

Removing DidLoseContext from the CommandBufferLocalClient.

+}
+
 gpu::Capabilities CommandBufferLocal::GetCapabilities() {
   DCHECK(CalledOnValidThread());
   return capabilities_;
 }
 
 int32_t CommandBufferLocal::CreateImage(ClientBuffer buffer,
                                         size_t width,
                                         size_t height,
                                         unsigned internal_format) {
   DCHECK(CalledOnValidThread());
@@ skipping 322 matching lines @@
     client_->UpdateVSyncParameters(timebase, interval);
 }
 
 void CommandBufferLocal::OnGpuCompletedSwapBuffersOnClientThread(
     gfx::SwapResult result) {
   if (client_)
     client_->GpuCompletedSwapBuffers(result);
 }
 
 }  // namespace mus