Hook up the resize rect for Mac and enable its use in the renderer (mac-only)...

chrome/browser/browser_window_controller.mm

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/browser.h"
 #import "chrome/browser/browser_window_cocoa.h"
 #import "chrome/browser/browser_window_controller.h"
 #import "chrome/browser/cocoa/tab_strip_view.h"
 #import "chrome/browser/cocoa/tab_strip_controller.h"
 
@@ skipping 127 matching lines @@
 - (void)updateToolbarWithContents:(TabContents*)tab
                shouldRestoreState:(BOOL)shouldRestore {
   [tabStripController_ updateToolbarWithContents:tab
                                  shouldRestoreState:shouldRestore];
 }
 
 - (void)setStarredState:(BOOL)isStarred {
   [tabStripController_ setStarredState:isStarred];
 }
 
+// Return the rect, in WebKit coordinates (flipped), of the window's grow box
+// in the coordinate system of the content area of the currently selected tab.
+// |windowGrowBox| needs to be in the window's coordinate system.
+- (NSRect)selectedTabGrowBoxFromWindowGrowBox:(NSRect)windowGrowBox {
+  return [tabStripController_ 
+              selectedTabGrowBoxFromWindowGrowBox:windowGrowBox];
+}
+
 @end