Add a second unsafe ES3 API in command buffer.

gpu/command_buffer/client/gles2_interface_stub_impl_autogen.h

Index: gpu/command_buffer/client/gles2_interface_stub_impl_autogen.h
diff --git a/gpu/command_buffer/client/gles2_interface_stub_impl_autogen.h b/gpu/command_buffer/client/gles2_interface_stub_impl_autogen.h
index 0f05f5596c65a0b80d514d1f666c4bd311c1ca9f..b53c1bf6456e2bf2e48120d0c19f9063357ecc99 100644
--- a/gpu/command_buffer/client/gles2_interface_stub_impl_autogen.h
+++ b/gpu/command_buffer/client/gles2_interface_stub_impl_autogen.h
@@ -99,6 +99,12 @@ void GLES2InterfaceStub::CompressedTexSubImage2D(GLenum /* target */,
                                                  GLsizei /* imageSize */,
                                                  const void* /* data */) {
 }
+void GLES2InterfaceStub::CopyBufferSubData(GLenum /* readtarget */,
+                                           GLenum /* writetarget */,
+                                           GLintptr /* readoffset */,
+                                           GLintptr /* writeoffset */,
+                                           GLsizeiptr /* size */) {
+}
 void GLES2InterfaceStub::CopyTexImage2D(GLenum /* target */,
                                         GLint /* level */,
                                         GLenum /* internalformat */,