[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;
+const CGFloat kBrowserFrameViewPaintHeight = 37.0;

[erikchen, 2016/09/20 23:07:47]

I imagine we'll need two variables, one for 10.11+, and one for 10.10-?

[shrike, 2016/09/20 23:27:17]

Ugh. My assumption is that the frame paint height is larger than it needs to be
for Material Design and so it's OK to make this change, but you may be right
about needing to special case this for 10.10 and below.

 
 // 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_;
@@ skipping 48 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_