Add ability to store hidpi theme images in data pack

chrome/browser/ui/cocoa/download/background_theme.mm

 // 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 "chrome/browser/ui/cocoa/download/background_theme.h"
 
 #import "chrome/browser/themes/theme_service.h"
 
 BackgroundTheme::BackgroundTheme(ui::ThemeProvider* provider) :
     provider_(provider) {
@@ skipping 33 matching lines @@
 }
 
 bool BackgroundTheme::ShouldUseNativeFrame() const {
   return false;
 }
 
 bool BackgroundTheme::HasCustomImage(int id) const {
   return false;
 }
 
-base::RefCountedMemory* BackgroundTheme::GetRawData(int id) const {
+base::RefCountedMemory* BackgroundTheme::GetRawData(
+    int id,
+    ui::ScaleFactor scale_factor) const {
   return NULL;
 }
 
 NSImage* BackgroundTheme::GetNSImageNamed(int id, bool allow_default) const {
   return nil;
 }
 
 NSColor* BackgroundTheme::GetNSImageColorNamed(int id,
                                                bool allow_default) const {
   return nil;
@@ skipping 17 matching lines @@
       return buttonGradient_.get();
     case ThemeService::GRADIENT_TOOLBAR_BUTTON_PRESSED:
     case ThemeService::GRADIENT_TOOLBAR_BUTTON_PRESSED_INACTIVE:
       return buttonPressedGradient_.get();
     default:
       return provider_->GetNSGradient(id);
   }
 }