Re-land: cc: Use worker context for one-copy tile initialization.

content/browser/compositor/gpu_process_transport_factory.cc

Index: content/browser/compositor/gpu_process_transport_factory.cc
diff --git a/content/browser/compositor/gpu_process_transport_factory.cc b/content/browser/compositor/gpu_process_transport_factory.cc
index f73e8a3015bf44e56d98e4dad6be4c67f223b508..a5ee594f4a2b33f8c0c53ddc6bc5c98812b96cf5 100644
--- a/content/browser/compositor/gpu_process_transport_factory.cc
+++ b/content/browser/compositor/gpu_process_transport_factory.cc
@@ -274,7 +274,8 @@ void GpuProcessTransportFactory::EstablishedGpuChannel(
         context_provider->ContextCapabilities();
     if (!data->surface_id) {
       surface = make_scoped_ptr(new OffscreenBrowserCompositorOutputSurface(
-          context_provider, compositor->vsync_manager(),
+          context_provider, SharedWorkerContextProvider(),
+          compositor->vsync_manager(),
           scoped_ptr<BrowserCompositorOverlayCandidateValidator>()));
     } else if (capabilities.gpu.surfaceless) {
       GLenum target = GL_TEXTURE_2D;
@@ -285,13 +286,15 @@ void GpuProcessTransportFactory::EstablishedGpuChannel(
 #endif
       surface =
           make_scoped_ptr(new GpuSurfacelessBrowserCompositorOutputSurface(
-              context_provider, data->surface_id, compositor->vsync_manager(),
+              context_provider, SharedWorkerContextProvider(), data->surface_id,
+              compositor->vsync_manager(),
               CreateOverlayCandidateValidator(compositor->widget()), target,
               format, BrowserGpuMemoryBufferManager::current()));
     } else {
       if (!surface) {
         surface = make_scoped_ptr(new GpuBrowserCompositorOutputSurface(
-            context_provider, compositor->vsync_manager(),
+            context_provider, SharedWorkerContextProvider(),
+            compositor->vsync_manager(),
             CreateOverlayCandidateValidator(compositor->widget())));
       }
     }
@@ -322,7 +325,8 @@ void GpuProcessTransportFactory::EstablishedGpuChannel(
 
   scoped_ptr<cc::SurfaceDisplayOutputSurface> output_surface(
       new cc::SurfaceDisplayOutputSurface(
-          manager, compositor->surface_id_allocator(), context_provider));
+          manager, compositor->surface_id_allocator(), context_provider,
+          SharedWorkerContextProvider()));
   display_client->set_surface_output_surface(output_surface.get());
   output_surface->set_display_client(display_client.get());
   display_client->display()->Resize(compositor->size());
@@ -520,6 +524,25 @@ GpuProcessTransportFactory::SharedMainThreadContextProvider() {
   return shared_main_thread_contexts_;
 }
 
+scoped_refptr<ContextProviderCommandBuffer>
+GpuProcessTransportFactory::SharedWorkerContextProvider() {
+  if (shared_worker_context_provider_.get())
+    return shared_worker_context_provider_;
+
+  shared_worker_context_provider_ = ContextProviderCommandBuffer::Create(
+      GpuProcessTransportFactory::CreateOffscreenCommandBufferContext(),
+      BROWSER_WORKER_CONTEXT);
+
+  if (shared_worker_context_provider_.get()) {
+    shared_worker_context_provider_->SetLostContextCallback(
+        base::Bind(&GpuProcessTransportFactory::OnLostWorkerSharedContext,
+                   callback_factory_.GetWeakPtr()));
+    if (!shared_worker_context_provider_->BindToCurrentThread())
+      shared_worker_context_provider_ = nullptr;
+  }
+  return shared_worker_context_provider_;
+}
+
 GpuProcessTransportFactory::PerCompositorData*
 GpuProcessTransportFactory::CreatePerCompositorData(
     ui::Compositor* compositor) {
@@ -601,4 +624,10 @@ void GpuProcessTransportFactory::OnLostMainThreadSharedContext() {
   lost_shared_main_thread_contexts  = NULL;
 }
 
+void GpuProcessTransportFactory::OnLostWorkerSharedContext() {
+  LOG(ERROR) << "Lost UI shared worker context.";
+
+  shared_worker_context_provider_ = nullptr;
+}
+
 }  // namespace content