Delete IsAtLeastOS10_9() and IsAtMostOS10_9()

ui/native_theme/native_theme_mac.mm

 // Copyright (c) 2013 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/native_theme/native_theme_mac.h"
 
 #import <Cocoa/Cocoa.h>
 #include <stddef.h>
 
 #include "base/mac/mac_util.h"
@@ skipping 170 matching lines @@
     case kColorId_DisabledEmphasizedMenuItemForegroundColor:
       return NSSystemColorToSkColor([NSColor disabledControlTextColor]);
     case kColorId_SelectedMenuItemForegroundColor:
       return NSSystemColorToSkColor([NSColor selectedMenuItemTextColor]);
     case kColorId_FocusedMenuItemBackgroundColor:
     case kColorId_HoverMenuItemBackgroundColor:
       return NSSystemColorToSkColor([NSColor selectedMenuItemColor]);
     case kColorId_MenuBackgroundColor:
       return kMenuPopupBackgroundColor;
     case kColorId_MenuSeparatorColor:
-      return base::mac::IsOS10_9() ? kMenuSeparatorColorMavericks
-                                   : kMenuSeparatorColor;
+      return base::mac::IsAtLeastOS10_10() ? kMenuSeparatorColor
+                                           : kMenuSeparatorColorMavericks;
     case kColorId_MenuBorderColor:
       return kMenuBorderColor;
 
     // Link.
     case kColorId_LinkDisabled:
       return SK_ColorBLACK;
     case kColorId_LinkEnabled:
       return SK_ColorBLUE;
     case kColorId_LinkPressed:
       return SK_ColorRED;
@@ skipping 40 matching lines @@
       return GetAuraColor(color_id, this);
   }
 }
 
 void NativeThemeMac::PaintMenuPopupBackground(
     SkCanvas* canvas,
     const gfx::Size& size,
     const MenuBackgroundExtraParams& menu_background) const {
   SkPaint paint;
   paint.setAntiAlias(true);
-  if (base::mac::IsOS10_9())
+  if (base::mac::IsAtLeastOS10_10())
+    paint.setColor(kMenuPopupBackgroundColor);
+  else
     paint.setColor(kMenuPopupBackgroundColorMavericks);
-  else
-    paint.setColor(kMenuPopupBackgroundColor);
   const SkScalar radius = SkIntToScalar(menu_background.corner_radius);
   SkRect rect = gfx::RectToSkRect(gfx::Rect(size));
   canvas->drawRoundRect(rect, radius, radius, paint);
 }
 
 void NativeThemeMac::PaintMenuItemBackground(
     SkCanvas* canvas,
     State state,
     const gfx::Rect& rect,
     const MenuItemExtraParams& menu_item) const {
@@ skipping 166 matching lines @@
   return ApplySystemControlTint(GetAuraColor(color_id, base_theme));
 }
 
 NativeThemeMac::NativeThemeMac() {
 }
 
 NativeThemeMac::~NativeThemeMac() {
 }
 
 }  // namespace ui