Subject .mm files to the header sorting presubmit

chrome/browser/themes/theme_service_mac.mm

 // Copyright (c) 2011 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/themes/theme_service.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/logging.h"
 #include "chrome/browser/themes/browser_theme_pack.h"
 #include "chrome/browser/themes/theme_properties.h"
 #include "skia/ext/skia_utils_mac.h"
 #import "third_party/google_toolbox_for_mac/src/AppKit/GTMNSColor+Luminance.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/image/image.h"
-#include "skia/ext/skia_utils_mac.h"
 
 NSString* const kBrowserThemeDidChangeNotification =
     @"BrowserThemeDidChangeNotification";
 
 typedef ThemeProperties Properties;
 
 namespace {
 
 void HSLToHSB(const color_utils::HSL& hsl, CGFloat* h, CGFloat* s, CGFloat* b) {
   SkColor color = color_utils::HSLToSkColor(hsl, 255);  // alpha doesn't matter
@@ skipping 252 matching lines @@
   }
   nscolor_cache_.clear();
 
   // Free gradients.
   for (NSGradientMap::iterator i = nsgradient_cache_.begin();
        i != nsgradient_cache_.end(); i++) {
     [i->second release];
   }
   nsgradient_cache_.clear();
 }