ImageSkia: don't force fallback to a supported scale when the image

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 <stddef.h>
 
 #include <algorithm>
 #include <cmath>
@@ skipping 201 matching lines @@
       smallest_diff = diff;
     }
   }
 
   if (fetch_new_image && source_.get()) {
     DCHECK(CalledOnValidThread())
         << "An ImageSkia with the source must be accessed by the same thread.";
 
     ImageSkiaRep image;
     float resource_scale = scale;
-    if (g_supported_scales) {
+    if (!HasRepresentationAtAllScales() && g_supported_scales) {
       if (g_supported_scales->back() <= scale) {
         resource_scale = g_supported_scales->back();
       } else {
         for (size_t i = 0; i < g_supported_scales->size(); ++i) {
           if ((*g_supported_scales)[i] + kFallbackToSmallerScaleDiff >= scale) {
             resource_scale = (*g_supported_scales)[i];
             break;
           }
         }
       }
@@ skipping 285 matching lines @@
 bool ImageSkia::CanModify() const {
   return !storage_.get() || storage_->CanModify();
 }
 
 void ImageSkia::DetachStorageFromThread() {
   if (storage_.get())
     storage_->DetachFromThread();
 }
 
 }  // namespace gfx