Improve BindBufferBase/BindBufferRange and a few other commands.

gpu/command_buffer/service/context_group.cc

Index: gpu/command_buffer/service/context_group.cc
diff --git a/gpu/command_buffer/service/context_group.cc b/gpu/command_buffer/service/context_group.cc
index e9af8837fe4949ac0f8f2645906491069b63f693..d918526ee9043aee8100e5d24e9fab11d982904f 100644
--- a/gpu/command_buffer/service/context_group.cc
+++ b/gpu/command_buffer/service/context_group.cc
@@ -408,5 +408,14 @@ bool ContextGroup::QueryGLFeatureU(
   return result;
 }
 
+bool ContextGroup::GetBufferServiceId(
+    GLuint client_id, GLuint* service_id) const {
+  Buffer* buffer = buffer_manager_->GetBuffer(client_id);
+  if (!buffer)
+    return false;
+  *service_id = buffer->service_id();
+  return true;
+}
+
 }  // namespace gles2
 }  // namespace gpu