Delete IsAtLeastOS10_9() and IsAtMostOS10_9()

chrome/browser/ui/cocoa/custom_frame_view_unittest.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.
 
 #import <Cocoa/Cocoa.h>
 #include <objc/runtime.h>
 
 #include "base/mac/mac_util.h"
 #include "base/mac/scoped_nsobject.h"
 #import "chrome/browser/ui/cocoa/custom_frame_view.h"
@@ skipping 10 matching lines @@
     view_.reset([[customFrameClass alloc] initWithFrame:frame]);
   }
 
   base::scoped_nsobject<NSView> view_;
 };
 
 //  Test to make sure our class modifications were successful.
 TEST_F(CustomFrameViewTest, SuccessfulClassModifications) {
   // In Yosemite, the fullscreen button replaces the zoom button. We no longer
   // need to swizzle out this AppKit private method.
-  if (!base::mac::IsOS10_9())
+  if (base::mac::IsAtLeastOS10_10())
     return;
 
   unsigned int count;
   BOOL foundSwizzledMethod = NO;
 
   Method* methods = class_copyMethodList([view_ class], &count);
   for (unsigned int i = 0; i < count; ++i) {
     SEL selector = method_getName(methods[i]);
     if (selector == @selector(_fullScreenButtonOriginOriginal))
       foundSwizzledMethod = YES;
   }
   EXPECT_TRUE(foundSwizzledMethod);
   free(methods);
 }