mac: Remove code that was only needed on 10.5

chrome/browser/ui/cocoa/hover_button.mm

 // Copyright (c) 2010 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.
 
 #import "chrome/browser/ui/cocoa/hover_button.h"
 
 #import "chrome/browser/ui/cocoa/tracking_area.h"
 
 @implementation HoverButton
 
@@ skipping 43 matching lines @@
   // http://crbug.com/31279
   [self checkImageState];
 }
 
 - (void)setTrackingEnabled:(BOOL)enabled {
   if (enabled) {
     trackingArea_.reset(
         [[CrTrackingArea alloc] initWithRect:[self bounds]
                                      options:NSTrackingMouseEnteredAndExited |
                                              NSTrackingActiveAlways
-                                proxiedOwner:self
+                                       owner:self
                                     userInfo:nil]);
     [self addTrackingArea:trackingArea_.get()];
 
     // If you have a separate window that overlaps the close button, and you
     // move the mouse directly over the close button without entering another
     // part of the tab strip, we don't get any mouseEntered event since the
     // tracking area was disabled when we entered.
     // Done with a delay of 0 because sometimes an event appears to be missed
     // between the activation of the tracking area and the call to
     // checkImageState resulting in the button state being incorrect.
@@ skipping 23 matching lines @@
   self.hoverState = NSPointInRect(mouseLoc, [self bounds]) ?
       kHoverStateMouseOver : kHoverStateNone;
 }
 
 - (void)setHoverState:(HoverState)state {
   hoverState_ = state;
   [self setNeedsDisplay:YES];
 }
 
 @end