Delete background tab IOSurfaces on Mac.

content/browser/renderer_host/render_widget_host_view_win.cc

Index: content/browser/renderer_host/render_widget_host_view_win.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_win.cc b/content/browser/renderer_host/render_widget_host_view_win.cc
index cad5c9b7823503b95a83ae3d4bd3e8ddd61e3309..a88311ec90801b5177721faa0add78e58d9d69e7 100644
--- a/content/browser/renderer_host/render_widget_host_view_win.cc
+++ b/content/browser/renderer_host/render_widget_host_view_win.cc
@@ -2251,6 +2251,14 @@ void RenderWidgetHostViewWin::AcceleratedSurfaceSuspend() {
     accelerated_surface_->Suspend();
 }
 
+bool RenderWidgetHostViewWin::HasAcceleratedSurface(
+      const gfx::Size& desired_size) {
+  // TODO(jbates) Implement this so this view can use GetBackingStore for both
+  // software and GPU frames. Defaulting to false just makes GetBackingStore
+  // only useable for software frames.
+  return false;
+}
+
 void RenderWidgetHostViewWin::SetAccessibilityFocus(int acc_obj_id) {
   if (!render_widget_host_)
     return;