Mac: Add off-screen rendering support (issue #518).

- Build with the 10.7 SDK (set GYP_DEFINES='mac_sdk=10.7') to include Retina support in the cefclient OSR example.

git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@1226 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

include/cef_render_handler.h

@@ -78,6 +78,19 @@ class CefRenderHandler : public virtual CefBase {
                               int& screenX,
                               int& screenY) { return false; }
 
+  ///
+  // Called to allow the client to fill in the CefScreenInfo object with
+  // appropriate values. Return true if the |screen_info| structure has been
+  // modified.
+  //
+  // If the screen info rectangle is left empty the rectangle from GetViewRect
+  // will be used. If the rectangle is still empty or invalid popups may not be
+  // drawn correctly.
+  ///
+  /*--cef()--*/
+  virtual bool GetScreenInfo(CefRefPtr<CefBrowser> browser,
+                             CefScreenInfo& screen_info) { return false; }
+
   ///
   // Called when the browser wants to show or hide the popup widget. The popup
   // should be shown if |show| is true and hidden if |show| is false.