gpu: Add flag for enabling asynchronous worker context.

content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h

Index: content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h
diff --git a/content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h b/content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h
index 7a930769f9ad8f6c4044b82ebdccec77b8ee70da..0da67e0d9d1111f7b4185f10954dc2cc482f47be 100644
--- a/content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h
+++ b/content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h
@@ -21,6 +21,7 @@
 #include "content/common/gpu/client/command_buffer_metrics.h"
 #include "gpu/command_buffer/common/gles2_cmd_utils.h"
 #include "gpu/ipc/client/command_buffer_proxy_impl.h"
+#include "gpu/ipc/common/gpu_stream_constants.h"
 #include "gpu/ipc/common/surface_handle.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 #include "ui/gl/gpu_preference.h"
@@ -67,7 +68,9 @@ class WebGraphicsContext3DCommandBufferImpl {
       const GURL& active_url,
       scoped_refptr<gpu::GpuChannelHost> host,
       gfx::GpuPreference gpu_preference,
-      bool automatic_flushes);
+      bool automatic_flushes,
+      int32_t stream_id,
+      gpu::GpuStreamPriority stream_priority);
 
   CONTENT_EXPORT ~WebGraphicsContext3DCommandBufferImpl();
 
@@ -123,14 +126,14 @@ class WebGraphicsContext3DCommandBufferImpl {
   bool initialize_failed_ = false;
   WebGraphicsContextLostCallback* context_lost_callback_ = nullptr;
 
-  bool automatic_flushes_;
-
   // State needed by MaybeInitializeGL.
   scoped_refptr<gpu::GpuChannelHost> host_;
   gpu::SurfaceHandle surface_handle_;
   GURL active_url_;
-
   gfx::GpuPreference gpu_preference_;
+  bool automatic_flushes_;
+  int32_t stream_id_;
+  gpu::GpuStreamPriority stream_priority_;
 
   std::unique_ptr<gpu::CommandBufferProxyImpl> command_buffer_;
   std::unique_ptr<gpu::gles2::GLES2CmdHelper> gles2_helper_;