[Mac] Avoid "adding unknown subview" warning.

chrome/browser/ui/cocoa/framed_browser_window.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_COCOA_FRAMED_BROWSER_WINDOW_H_
 #define CHROME_BROWSER_UI_COCOA_FRAMED_BROWSER_WINDOW_H_
 
 #import <Cocoa/Cocoa.h>
 
 #include "chrome/browser/ui/cocoa/chrome_browser_window.h"
 
 // Offsets from the top/left of the window frame to the top of the window
 // controls (zoom, close, miniaturize) for a window with a tabstrip.
 const NSInteger kFramedWindowButtonsWithTabStripOffsetFromTop = 11;
 const NSInteger kFramedWindowButtonsWithTabStripOffsetFromLeft = 11;
 
 // Offsets from the top/left of the window frame to the top of the window
 // controls (zoom, close, miniaturize) for a window without a tabstrip.
 const NSInteger kFramedWindowButtonsWithoutTabStripOffsetFromTop = 4;
 const NSInteger kFramedWindowButtonsWithoutTabStripOffsetFromLeft = 8;
 
-// The amount of window background image that is painted at the top of the
-// window, so that it shows behind the tap strip area.
-const CGFloat kBrowserFrameViewPaintHeight = 60.0;
-
 // Cocoa class representing a framed browser window.
 // We need to override NSWindow with our own class since we need access to all
 // unhandled keyboard events and subclassing NSWindow is the only method to do
 // this. We also handle our own window controls and custom window frame drawing.
 @interface FramedBrowserWindow : ChromeBrowserWindow {
  @private
   BOOL shouldHideTitle_;
   BOOL hasTabStrip_;
   NSButton* closeButton_;
   NSButton* miniaturizeButton_;
   NSButton* zoomButton_;
 
   // Locks the window's frame and style mask. If it's set to YES, then the
   // frame and the style mask cannot be changed.
   BOOL styleMaskLock_;
 
   CGFloat windowButtonsInterButtonSpacing_;
 }
 
+// The amount of window background image that is painted at the top of the
+// window, so that it shows behind the tap strip area.
++ (CGFloat)browserFrameViewPaintHeight;
+
 // Designated initializer.
 - (id)initWithContentRect:(NSRect)contentRect
               hasTabStrip:(BOOL)hasTabStrip;
 
 // Tells the window to suppress title drawing.
 - (void)setShouldHideTitle:(BOOL)flag;
 
 // When the lock is set to YES, the frame and style mask of the Window cannot be
 // changed. This is used to prevent AppKit from making these unwanted changes
 // to the window during exit fullscreen transition. It is very important to
@@ skipping 28 matching lines @@
 
 // Undocumented Cocoa API to suppress drawing of the window's title.
 // -setTitle: still works, but the title set only applies to the
 // miniwindow and menus (and, importantly, Expose).  Overridden to
 // return |shouldHideTitle_|.
 -(BOOL)_isTitleHidden;
 
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_FRAMED_BROWSER_WINDOW_H_