Avoid destroying surface before the parent surface stops referencing it.

mojo/services/view_manager/context_factory_impl.h

Index: mojo/services/view_manager/context_factory_impl.h
diff --git a/mojo/services/view_manager/context_factory_impl.h b/mojo/services/view_manager/context_factory_impl.h
index 0ef0fe3c2690376e7f23f2e5ca720eefd8d27c92..122fa1e4c0c459f32a17a2711805a8e8ec3d7f26 100644
--- a/mojo/services/view_manager/context_factory_impl.h
+++ b/mojo/services/view_manager/context_factory_impl.h
@@ -38,12 +38,15 @@ class ContextFactoryImpl : public ui::ContextFactory {
   virtual bool DoesCreateTestContexts() OVERRIDE;
   virtual cc::SharedBitmapManager* GetSharedBitmapManager() OVERRIDE;
   virtual base::MessageLoopProxy* GetCompositorMessageLoop() OVERRIDE;
+  virtual scoped_ptr<cc::SurfaceIdAllocator> CreateSurfaceIdAllocator()
+      OVERRIDE;
 
  private:
   scoped_refptr<webkit::gpu::ContextProviderInProcess>
       shared_main_thread_contexts_;
 
   ScopedMessagePipeHandle command_buffer_handle_;
+  uint32_t next_surface_id_namespace_;
 
   // TODO(sky): for debugging, remove.
   bool did_create_;