Introduces ImageSkia::GetRepresentations() for Mac

ui/gfx/image/image_skia.cc

 // 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.
 
 #include "ui/gfx/image/image_skia.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 
@@ skipping 35 matching lines @@
 // A helper class such that ImageSkia can be cheaply copied. ImageSkia holds a
 // refptr instance of ImageSkiaStorage, which in turn holds all of ImageSkia's
 // information.
 class ImageSkiaStorage : public base::RefCounted<ImageSkiaStorage> {
  public:
   ImageSkiaStorage(ImageSkiaSource* source, const gfx::Size& size)
       : source_(source),
         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_; }
 
   // Returns the iterator of the image rep whose density best matches
   // |scale_factor|. If the image for the |scale_factor| doesn't exist
   // in the storage and |storage| is set, it fetches new image by calling
   // |ImageSkiaSource::GetImageForScale|. If the source returns the
   // image with different scale factor (if the image doesn't exist in
   // resource, for example), it will fallback to closest image rep.
@@ skipping 140 matching lines @@
   if (isNull())
     return NullImageRep();
 
   ImageSkiaReps::iterator it = storage_->FindRepresentation(scale_factor, true);
   if (it == storage_->image_reps().end())
     return NullImageRep();
 
   return *it;
 }
 
+#if defined(OS_MACOSX)
+
+std::vector<ImageSkiaRep> ImageSkia::GetRepresentations() const {
+  if (isNull())
+    return std::vector<ImageSkiaRep>();
+
+  if (!storage_->has_source())
+    return image_reps();
+
+  // Attempt to generate image reps for as many scale factors supported by
+  // this platform as possible.
+  // Do not build return array here because the mapping from scale factor to
+  // image rep is one to many in some cases.
+  std::vector<ui::ScaleFactor> supported_scale_factors =
+      ui::GetSupportedScaleFactors();
+  for (size_t i = 0; i < supported_scale_factors.size(); ++i)
+    storage_->FindRepresentation(supported_scale_factors[i], true);
+
+  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;
+}
+
+#endif  // OS_MACOSX
+
 bool ImageSkia::empty() const {
   return isNull() || storage_->size().IsEmpty();
 }
 
 int ImageSkia::width() const {
   return isNull() ? 0 : storage_->size().width();
 }
 
 gfx::Size ImageSkia::size() const {
   return gfx::Size(width(), height());
@@ skipping 54 matching lines @@
   if (image_rep.sk_bitmap().empty()) {
     storage_ = NULL;
     return;
   }
   storage_ = new internal::ImageSkiaStorage(
       NULL, gfx::Size(image_rep.GetWidth(), image_rep.GetHeight()));
   storage_->image_reps().push_back(image_rep);
 }
 
 }  // namespace gfx