mac: Use NSWidth() and friends in a few more places.

ui/base/cocoa/underlay_opengl_hosting_window.mm

 // Copyright (c) 2012 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 "ui/base/cocoa/underlay_opengl_hosting_window.h"
 
 #import <objc/runtime.h>
 
 #include "base/logging.h"
 #include "base/mac/mac_util.h"
@@ skipping 81 matching lines @@
   // - It causes console spew: <http://crbug.com/78973>
   // - It breaks Expose: <http://sourceforge.net/projects/heat-meteo/forums/forum/268087/topic/4582610>
   //
   // This is a banned practice
   // <http://www.chromium.org/developers/coding-style/cocoa-dos-and-donts>. Do
   // not do this. Use kWindowSizeDeterminedLater in
   // ui/base/cocoa/window_size_constants.h instead.
   //
   // (This is checked here because UnderlayOpenGLHostingWindow is the base of
   // most Chromium windows, not because this is related to its functionality.)
-  DCHECK(contentRect.size.width > 0 &&
-         contentRect.size.height > 0);
+  DCHECK(!NSIsEmptyRect(contentRect));
   if ((self = [super initWithContentRect:contentRect
                                styleMask:windowStyle
                                  backing:bufferingType
                                    defer:deferCreation])) {
     if (base::mac::IsOSSnowLeopardOrLater()) {
       // Hole punching is used when IOSurfaces are used to transport, which is
       // only on > 10.5. Therefore, on > 10.5, the window must always be
       // non-opaque whether or not it's titled if we want hole punching to work.
       [self setOpaque:NO];
 
@@ skipping 28 matching lines @@
         [rightOpaque setAlphaValue:kAlphaValueJustOpaqueEnough];
         [rootView addSubview:rightOpaque];
       }
     }
   }
 
   return self;
 }
 
 @end