Remove Widget::OnRootViewLayout().

ui/views/widget/native_widget_mac.mm

 // Copyright 2014 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/views/widget/native_widget_mac.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include <utility>
 
@@ skipping 585 matching lines @@
 
 void NativeWidgetMac::SetVisibilityAnimationTransition(
     Widget::VisibilityTransition transition) {
   NOTIMPLEMENTED();
 }
 
 ui::NativeTheme* NativeWidgetMac::GetNativeTheme() const {
   return ui::NativeThemeMac::instance();
 }
 
-void NativeWidgetMac::OnRootViewLayout() {}
-
 bool NativeWidgetMac::IsTranslucentWindowOpacitySupported() const {
   return false;
 }
 
 void NativeWidgetMac::OnSizeConstraintsChanged() {
   bridge_->OnSizeConstraintsChanged();
 }
 
 void NativeWidgetMac::RepostNativeEvent(gfx::NativeEvent native_event) {
   NOTIMPLEMENTED();
@@ skipping 150 matching lines @@
   [[ViewsNSWindowCloseAnimator alloc] initWithWindow:window];
 }
 
 - (void)animationDidEnd:(NSAnimation*)animation {
   [window_ close];
   [animation_ setDelegate:nil];
   [self release];
 }
 
 @end