Add support for multi resolution icons

ui/base/resource/resource_bundle_mac.mm

Index: ui/base/resource/resource_bundle_mac.mm
diff --git a/ui/base/resource/resource_bundle_mac.mm b/ui/base/resource/resource_bundle_mac.mm
index 1a238a72c08d230a14f6863ce180027f2fd76086..3e04df9cd5b5a9f1022f7a5c2cfcb8768ddc2838 100644
--- a/ui/base/resource/resource_bundle_mac.mm
+++ b/ui/base/resource/resource_bundle_mac.mm
@@ -62,19 +62,9 @@ FilePath ResourceBundle::GetLocaleFilePath(const std::string& app_locale) {
 
 gfx::Image& ResourceBundle::GetNativeImageNamed(int resource_id) {
   // Check to see if the image is already in the cache.
-  {
-    base::AutoLock lock(*lock_);
-    ImageMap::const_iterator found = images_.find(resource_id);
-    if (found != images_.end()) {
-      if (!found->second->HasRepresentation(gfx::Image::kNSImageRep)) {
-        DLOG(WARNING) << "ResourceBundle::GetNativeImageNamed() is returning a"
-          << " cached gfx::Image that isn't backed by an NSImage. The image"
-          << " will be converted, rather than going through the NSImage loader."
-          << " resource_id = " << resource_id;
-      }
-      return *found->second;
-    }
-  }
+  std::vector<gfx::Image*> images;
+  if (GetImagesFromCacheNamed(resource_id, images) && !images.empty())
+    return **images.begin();
 
   // Load the raw data from the resource pack.
   scoped_refptr<RefCountedStaticMemory> data(
@@ -89,16 +79,21 @@ gfx::Image& ResourceBundle::GetNativeImageNamed(int resource_id) {
 
   // Cache the converted image.
   if (ns_image.get()) {
-    base::AutoLock lock(*lock_);
-
-    // Another thread raced the load and has already cached the image.
-    if (images_.count(resource_id)) {
-      return *images_[resource_id];
+    {
+      base::AutoLock lock(*lock_);
+
+      // Has another thread raced the load and has already cached the image?
+      if (!images_.count(resource_id)) {
+        gfx::Image* image = new gfx::Image(ns_image.release());
+        std::vector<gfx::Image*>* images_ptr = new std::vector<gfx::Image*>;
+        images_ptr->push_back(image);
+        images_[resource_id] = images_ptr;
+        return *image;
+      }
     }
 
-    gfx::Image* image = new gfx::Image(ns_image.release());
-    images_[resource_id] = image;
-    return *image;
+    if (GetImagesFromCacheNamed(resource_id, images) && !images.empty())
+      return **images.begin();
   }
 
   LOG(WARNING) << "Unable to load image with id " << resource_id;