Implement offscreenCanvas.getContext('webgl') on a worker thread

content/renderer/webgraphicscontext3d_provider_impl.cc

Index: content/renderer/webgraphicscontext3d_provider_impl.cc
diff --git a/content/renderer/webgraphicscontext3d_provider_impl.cc b/content/renderer/webgraphicscontext3d_provider_impl.cc
index 17f34bc3a8ffbca219da56ec8ecf0e72a2f89b3e..e5654439b546f994d4d654631dc1bcd560343c29 100644
--- a/content/renderer/webgraphicscontext3d_provider_impl.cc
+++ b/content/renderer/webgraphicscontext3d_provider_impl.cc
@@ -6,6 +6,7 @@
 
 #include "content/common/gpu/client/context_provider_command_buffer.h"
 #include "gpu/command_buffer/client/context_support.h"
+#include "gpu/ipc/client/command_buffer_proxy_impl.h"
 #include "third_party/WebKit/public/platform/functional/WebFunction.h"
 
 namespace content {
@@ -20,6 +21,10 @@ gpu::gles2::GLES2Interface* WebGraphicsContext3DProviderImpl::contextGL() {
   return provider_->ContextGL();
 }
 
+bool WebGraphicsContext3DProviderImpl::BindToCurrentThread() {
+  return provider_->BindToCurrentThread();
+}
+
 GrContext* WebGraphicsContext3DProviderImpl::grContext() {
   return provider_->GrContext();
 }