[Mac] Avoid "adding unknown subview" warning.

chrome/browser/ui/cocoa/browser_window_layout.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_COCOA_BROWSER_WINDOW_CONTROLLER_LAYOUT_H_
 #define CHROME_BROWSER_UI_COCOA_BROWSER_WINDOW_CONTROLLER_LAYOUT_H_
 
 #import <Cocoa/Cocoa.h>
 
 #import "chrome/browser/ui/cocoa/fullscreen_toolbar_controller.h"
 
 namespace chrome {
 
 // The height of the tab strip.
 extern const CGFloat kTabStripHeight;
 
+// Returns true if windows should use NSFullSizeContentViewWindowMask style
+// mask.
+bool ShouldUseFullSizeContentView();
+
 // The parameters used to calculate the layout of the views managed by the
 // BrowserWindowController.
 struct LayoutParameters {
   // The size of the content view of the window.
   NSSize contentViewSize;
   // The size of the window.
   NSSize windowSize;
 
   // Whether the controller is in any fullscreen mode. This parameter should be
   // NO if the controller is in the process of entering fullscreen.
@@ skipping 146 matching lines @@
 
 - (void)setHasDownloadShelf:(BOOL)hasDownloadShelf;
 - (void)setDownloadShelfHeight:(CGFloat)downloadShelfHeight;
 @end
 
 @interface BrowserWindowLayout (ExposedForTesting)
 - (void)setOSYosemiteOrLater:(BOOL)osYosemiteOrLater;
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_BROWSER_WINDOW_CONTROLLER_LAYOUT_H_