Use native Cocoa tooltips instead of Mozilla's ToolTip class.

third_party/mozilla/include/ToolTip.h

Index: third_party/mozilla/include/ToolTip.h
===================================================================
--- third_party/mozilla/include/ToolTip.h	(revision 19944)
+++ third_party/mozilla/include/ToolTip.h	(working copy)
@@ -1,57 +0,0 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* ***** BEGIN LICENSE BLOCK *****
- * Version: MPL 1.1/GPL 2.0/LGPL 2.1
- *
- * The contents of this file are subject to the Mozilla Public License Version
- * 1.1 (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- * http://www.mozilla.org/MPL/
- *
- * Software distributed under the License is distributed on an "AS IS" basis,
- * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
- * for the specific language governing rights and limitations under the
- * License.
- *
- * The Original Code is mozilla.org code.
- *
- * The Initial Developer of the Original Code is
- * Netscape Communications Corporation.
- * Portions created by the Initial Developer are Copyright (C) 2002
- * the Initial Developer. All Rights Reserved.
- *
- * Contributor(s):
- *   Richard Schreyer
- *   Josh Aas <josh@mozilla.com>
- *
- * Alternatively, the contents of this file may be used under the terms of
- * either the GNU General Public License Version 2 or later (the "GPL"), or
- * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
- * in which case the provisions of the GPL or the LGPL are applicable instead
- * of those above. If you wish to allow use of your version of this file only
- * under the terms of either the GPL or the LGPL, and not to allow others to
- * use your version of this file under the terms of the MPL, indicate your
- * decision by deleting the provisions above and replace them with the notice
- * and other provisions required by the GPL or the LGPL. If you do not delete
- * the provisions above, a recipient may use your version of this file under
- * the terms of any one of the MPL, the GPL or the LGPL.
- *
- * ***** END LICENSE BLOCK ***** */
-
-#import <Cocoa/Cocoa.h>
-
-@class ToolTipView;
-
-@interface ToolTip : NSObject
-{
-  NSWindow*     mTooltipWindow;
-  NSTextField*  mTextField;
-  NSTextView*   mTextView;
-}
-
-// Display a tooltip at |point| (in window coordinates) in |inWindow|.
-- (void)showToolTipAtPoint:(NSPoint)point
-                withString:(NSString*)string
-                overWindow:(NSWindow*)inWindow;
-- (void)closeToolTip;
-
-@end