Add ability to store hidpi theme images in data pack

ui/gfx/image/image_skia.cc

Index: ui/gfx/image/image_skia.cc
diff --git a/ui/gfx/image/image_skia.cc b/ui/gfx/image/image_skia.cc
index fadd2e606236a00ef3e76e9d5bda7804067e8778..327000983dafcf86d16ec666c6f8c4e81764b3ac 100644
--- a/ui/gfx/image/image_skia.cc
+++ b/ui/gfx/image/image_skia.cc
@@ -53,6 +53,8 @@ class ImageSkiaStorage : public base::RefCounted<ImageSkiaStorage> {
         size_(size) {
   }
 
+  bool has_source() const { return source_.get() != NULL; }
+
   std::vector<gfx::ImageSkiaRep>& image_reps() { return image_reps_; }
 
   const gfx::Size& size() const { return size_; }
@@ -260,7 +262,17 @@ std::vector<ImageSkiaRep> ImageSkia::image_reps() const {
   if (isNull())
     return std::vector<ImageSkiaRep>();
 
-  return storage_->image_reps();
+  ImageSkiaReps internal_image_reps = storage_->image_reps();
+  // Create list of image reps to return, skipping null image reps which were
+  // added for caching purposes only.
+  ImageSkiaReps image_reps;
+  for (ImageSkiaReps::iterator it = internal_image_reps.begin();
+       it != internal_image_reps.end(); ++it) {
+    if (!it->is_null())
+      image_reps.push_back(*it);
+  }
+
+  return image_reps;
 }
 
 const SkBitmap* ImageSkia::bitmap() const {