Order the GL overlays above windows if possible.

content/browser/renderer_host/compositing_iosurface_mac.h

Index: content/browser/renderer_host/compositing_iosurface_mac.h
diff --git a/content/browser/renderer_host/compositing_iosurface_mac.h b/content/browser/renderer_host/compositing_iosurface_mac.h
index 323ab75487d2ded0a50e6cf513f93b701ff2ffea..06ef58bcc54b2d0c74bb94a9e390cb7d3438ee20 100644
--- a/content/browser/renderer_host/compositing_iosurface_mac.h
+++ b/content/browser/renderer_host/compositing_iosurface_mac.h
@@ -32,8 +32,9 @@ namespace content {
 // RenderWidgetHostViewCocoa for blitting the IOSurface.
 class CompositingIOSurfaceMac {
  public:
-  // Returns NULL if IOSurface support is missing or GL APIs fail.
-  static CompositingIOSurfaceMac* Create();
+  // Returns NULL if IOSurface support is missing or GL APIs fail. Pass |true|
+  // to |below_window| if the surface should be ordered below the window.
+  static CompositingIOSurfaceMac* Create(bool below_window);

[Nico, 2012/11/29 22:23:13]

nit: enum parameters read better at the calling site than bool parameters.

("enum CreationMode { BelowWindow, Above Window };" or similar)

[Avi (use Gerrit), 2012/11/30 04:06:02]

Done.

   ~CompositingIOSurfaceMac();
 
   // Set IOSurface that will be drawn on the next NSView drawRect.