GLInProcessContext: support async flushes and dedicated GPU thread

gpu/command_buffer/client/gl_in_process_context.h

Index: gpu/command_buffer/client/gl_in_process_context.h
diff --git a/gpu/command_buffer/client/gl_in_process_context.h b/gpu/command_buffer/client/gl_in_process_context.h
index c4fb70f6daf371f38b13c36e3ff03509594be2bd..c5f684c00250f4b2225f34e4b8d9e93c98095e81 100644
--- a/gpu/command_buffer/client/gl_in_process_context.h
+++ b/gpu/command_buffer/client/gl_in_process_context.h
@@ -31,10 +31,6 @@ class GLES2_IMPL_EXPORT GLInProcessContext {
       int width, int height);
   static void SetGpuMemoryBufferCreator(GpuMemoryBufferCreator* creator);
 
-  // Must be called before any GLInProcessContext instances are created.
-  // Default value is false.
-  static void EnableVirtualizedContext();
-
   // GLInProcessContext configuration attributes. These are the same as used by
   // EGL. Attributes are matched using a closest fit algorithm.
   enum Attribute {