Add subscribeUniform extension pipeline

gpu/command_buffer/service/context_group.h

Index: gpu/command_buffer/service/context_group.h
diff --git a/gpu/command_buffer/service/context_group.h b/gpu/command_buffer/service/context_group.h
index ae4550cbda0dfc9397d8dafc271ae9afd94de580..eb53252806783812af9e87764def0441bfcddb52 100644
--- a/gpu/command_buffer/service/context_group.h
+++ b/gpu/command_buffer/service/context_group.h
@@ -34,6 +34,7 @@ class RenderbufferManager;
 class ProgramManager;
 class ShaderManager;
 class TextureManager;
+class ValuebufferManager;
 class MemoryTracker;
 struct DisallowedFeatures;
 
@@ -126,6 +127,10 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
     return renderbuffer_manager_.get();
   }
 
+  ValuebufferManager* valuebuffer_manager() const {
+    return valuebuffer_manager_.get();
+  }
+
   TextureManager* texture_manager() const {
     return texture_manager_.get();
   }
@@ -199,6 +204,8 @@ class GPU_EXPORT ContextGroup : public base::RefCounted<ContextGroup> {
 
   scoped_ptr<RenderbufferManager> renderbuffer_manager_;
 
+  scoped_ptr<ValuebufferManager> valuebuffer_manager_;
+
   scoped_ptr<TextureManager> texture_manager_;
 
   scoped_ptr<ProgramManager> program_manager_;