Implement GetIntegerv(SAMPLER_BINDING/TRANSFORM_FEEDBACK_BINDING) in command buffer.

gpu/command_buffer/service/sampler_manager.h

Index: gpu/command_buffer/service/sampler_manager.h
diff --git a/gpu/command_buffer/service/sampler_manager.h b/gpu/command_buffer/service/sampler_manager.h
index 8d8534328a588b146ff0b03195f00f429f1147f8..61c51160044f0719b44b6da786582ff93b77c081 100644
--- a/gpu/command_buffer/service/sampler_manager.h
+++ b/gpu/command_buffer/service/sampler_manager.h
@@ -37,9 +37,12 @@ struct SamplerState {
 
 class GPU_EXPORT Sampler : public base::RefCounted<Sampler> {
  public:
-  Sampler(SamplerManager* manager, GLuint service_id);
+  Sampler(SamplerManager* manager, GLuint client_id, GLuint service_id);
+
+  GLuint client_id() const {
+    return client_id_;
+  }
 
-  // The service side OpenGL id of the texture.
   GLuint service_id() const {
     return service_id_;
   }
@@ -114,7 +117,7 @@ class GPU_EXPORT Sampler : public base::RefCounted<Sampler> {
   // The manager that owns this Sampler.
   SamplerManager* manager_;
 
-    // The id of the texure
+  GLuint client_id_;
   GLuint service_id_;
 
   // Sampler parameters.