Makes ui::GetSupportedScaleFactors available on platforms other than Mac

ui/base/layout_mac.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 "ui/base/layout.h"
 
 #include <Cocoa/Cocoa.h>
 
 @interface NSScreen (LionAPI)
 - (CGFloat)backingScaleFactor;
 @end
 
 @interface NSWindow (LionAPI)
 - (CGFloat)backingScaleFactor;
 @end
 
 namespace {
 
-std::vector<ui::ScaleFactor>& GetSupportedScaleFactorsInternal() {
-  static std::vector<ui::ScaleFactor>* supported_scale_factors =
-      new std::vector<ui::ScaleFactor>();
-  if (supported_scale_factors->empty()) {
-    supported_scale_factors->push_back(ui::SCALE_FACTOR_100P);
-    supported_scale_factors->push_back(ui::SCALE_FACTOR_200P);
-  }
-  return *supported_scale_factors;
-}
-
 float GetScaleFactorScaleForNativeView(gfx::NativeView view) {
   float scale_factor = 1.0f;
   if (NSWindow* window = [view window]) {
     if ([window respondsToSelector:@selector(backingScaleFactor)])
       return [window backingScaleFactor];
     scale_factor = [window userSpaceScaleFactor];
   }
   if (NSScreen* screen = [NSScreen mainScreen]) {
     if ([screen respondsToSelector:@selector(backingScaleFactor)])
       return [screen backingScaleFactor];
     return [screen userSpaceScaleFactor];
   }
   return 1.0f;
 }
 
 }  // namespace
 
 namespace ui {
 
 ScaleFactor GetScaleFactorForNativeView(gfx::NativeView view) {
   return GetScaleFactorFromScale(GetScaleFactorScaleForNativeView(view));
 }
 
-std::vector<ScaleFactor> GetSupportedScaleFactors() {
-  return GetSupportedScaleFactorsInternal();
-}
-
-namespace test {
-
-void SetSupportedScaleFactors(
-    const std::vector<ui::ScaleFactor>& scale_factors) {
-  std::vector<ui::ScaleFactor>& supported_scale_factors =
-      GetSupportedScaleFactorsInternal();
-  supported_scale_factors = scale_factors;
-}
-
-}  // namespace test
-
 }  // namespace ui