diff --git a/components/exo/surface.h b/components/exo/surface.h
index 7dabdda..6c9fa64c 100644
--- a/components/exo/surface.h
+++ b/components/exo/surface.h
@@ -194,7 +194,7 @@
   void SetBeginFrameSource(cc::BeginFrameSource* begin_frame_source);
 
   // Returns the active contents size.
-  gfx::Size content_size() const { return content_size_; }
+  const gfx::Size& content_size() const { return content_size_; }
 
   // Returns true if the associated window is in 'stylus-only' mode.
   bool IsStylusOnly();