vr/gpu: BrowserGpuChannelHostFactory should be called on the same thread.

content/browser/renderer_host/compositor_impl_android.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/renderer_host/compositor_impl_android.h"
 
 #include <android/bitmap.h>
 #include <android/native_window_jni.h>
 #include <stdint.h>
 #include <unordered_set>
@@ skipping 41 matching lines @@
 #include "components/viz/service/display_embedder/server_shared_bitmap_manager.h"
 #include "components/viz/service/frame_sinks/frame_sink_manager_impl.h"
 #include "content/browser/compositor/surface_utils.h"
 #include "content/browser/gpu/browser_gpu_channel_host_factory.h"
 #include "content/browser/gpu/browser_gpu_memory_buffer_manager.h"
 #include "content/browser/gpu/compositor_util.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/common/gpu_stream_constants.h"
 #include "content/public/browser/android/compositor.h"
 #include "content/public/browser/android/compositor_client.h"
+#include "content/public/browser/browser_thread.h"
 #include "content/public/common/content_switches.h"
 #include "gpu/command_buffer/client/context_support.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
 #include "gpu/ipc/client/command_buffer_proxy_impl.h"
 #include "gpu/ipc/client/gpu_channel_host.h"
 #include "gpu/ipc/common/gpu_surface_tracker.h"
 #include "gpu/vulkan/features.h"
 #include "gpu/vulkan/vulkan_surface.h"
 #include "services/ui/public/cpp/gpu/context_provider_command_buffer.h"
 #include "third_party/khronos/GLES2/gl2.h"
@@ skipping 330 matching lines @@
   DCHECK(!CompositorImpl::IsInitialized());
   g_initialized = true;
 }
 
 // static
 void Compositor::CreateContextProvider(
     gpu::SurfaceHandle handle,
     gpu::gles2::ContextCreationAttribHelper attributes,
     gpu::SharedMemoryLimits shared_memory_limits,
     ContextProviderCallback callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
   BrowserGpuChannelHostFactory::instance()->EstablishGpuChannel(
       base::Bind(&CreateContextProviderAfterGpuChannelEstablished, handle,
                  attributes, shared_memory_limits, callback));
 }
 
 // static
 cc::SurfaceManager* CompositorImpl::GetSurfaceManager() {
   return g_compositor_dependencies.Get().frame_sink_manager->surface_manager();
 }
 
@@ skipping 484 matching lines @@
   }
   GetSurfaceManager()->UnregisterFrameSinkHierarchy(frame_sink_id_,
                                                     frame_sink_id);
 }
 
 bool CompositorImpl::HavePendingReadbacks() {
   return !readback_layer_tree_->children().empty();
 }
 
 }  // namespace content