Add support for multi resolution icons

chrome/browser/themes/theme_service_mac.mm

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/themes/theme_service.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/logging.h"
 #include "chrome/browser/themes/browser_theme_pack.h"
@@ skipping 26 matching lines @@
 
   // Check to see if we already have the image in the cache.
   NSImageMap::const_iterator nsimage_iter = nsimage_cache_.find(id);
   if (nsimage_iter != nsimage_cache_.end())
     return nsimage_iter->second;
 
   // Why don't we load the file directly into the image instead of the whole
   // SkBitmap > native conversion?
   // - For consistency with other platforms.
   // - To get the generated tinted images.
-  SkBitmap* bitmap = GetBitmapNamed(id);
-  NSImage* nsimage = gfx::SkBitmapToNSImage(*bitmap);
+  std::vector<SkBitmap*> bitmaps;
+  if (GetBitmapsNamed(id, bitmaps)) {
+    NSImage* nsimage = gfx::SkBitmapsToNSImage(bitmaps);
 
-  // We loaded successfully.  Cache the image.
-  if (nsimage) {
-    nsimage_cache_[id] = [nsimage retain];
-    return nsimage;
+    // We loaded successfully.  Cache the image.
+    if (nsimage) {
+      nsimage_cache_[id] = [nsimage retain];
+      return nsimage;
+    }
   }
 
   // We failed to retrieve the bitmap, show a debugging red square.
   LOG(WARNING) << "Unable to load NSImage with id " << id;
   NOTREACHED();  // Want to assert in debug mode.
 
   static NSImage* empty_image = NULL;
   if (!empty_image) {
     // The placeholder image is bright red so people notice the problem.  This
     // image will be leaked, but this code should never be hit.
@@ skipping 240 matching lines @@
   }
   nscolor_cache_.clear();
 
   // Free gradients.
   for (NSGradientMap::iterator i = nsgradient_cache_.begin();
        i != nsgradient_cache_.end(); i++) {
     [i->second release];
   }
   nsgradient_cache_.clear();
 }