mac: Remove code that was only needed on 10.5

chrome/browser/ui/cocoa/wrench_menu/menu_tracked_button.mm

 // Copyright (c) 2011 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/wrench_menu/menu_tracked_button.h"
 
 #include "base/mac/mac_util.h"
 
 @interface MenuTrackedButton (Private)
 - (void)doHighlight:(BOOL)highlight;
 - (void)checkMouseInRect;
 - (NSRect)insetBounds;
-- (BOOL)shouldHighlightOnHover;
 @end
 
 @implementation MenuTrackedButton
 
 @synthesize tracking = tracking_;
 
 - (void)updateTrackingAreas {
   [super updateTrackingAreas];
   [self removeTrackingRect:trackingTag_];
   trackingTag_ = [self addTrackingRect:NSInsetRect([self bounds], 1, 1)
@@ skipping 27 matching lines @@
 
   NSPoint point = [self convertPoint:[theEvent locationInWindow] fromView:nil];
   BOOL highlight = NSPointInRect(point, [self insetBounds]);
   [self doHighlight:highlight];
 
   // If tracking in non-sticky mode, poll the mouse cursor to see if it is still
   // over the button and thus needs to be highlighted.  The delay is the
   // smallest that still produces the effect while minimizing jank. Smaller
   // values make the selector fire too close to immediately/now for the mouse to
   // have moved off the receiver, and larger values produce lag.
-  if (tracking_ && [self shouldHighlightOnHover]) {
+  if (tracking_) {
     [self performSelector:@selector(checkMouseInRect)
                withObject:nil
                afterDelay:0.05
                   inModes:[NSArray arrayWithObject:NSEventTrackingRunLoopMode]];
   }
   [super mouseDragged:theEvent];
 }
 
 - (void)mouseUp:(NSEvent*)theEvent {
   [self doHighlight:NO];
   if (!tracking_) {
     return [super mouseUp:theEvent];
   }
   [self performClick:self];
   tracking_ = NO;
 }
 
 - (void)doHighlight:(BOOL)highlight {
-  if (![self shouldHighlightOnHover]) {
-    return;
-  }
   [[self cell] setHighlighted:highlight];
   [self setNeedsDisplay];
 }
 
 // Checks if the user's current mouse location is over this button.  If it is,
 // the user is merely hovering here.  If it is not, then disable the highlight.
 // If the menu is opened in non-sticky mode, the button does not receive enter/
 // exit mouse events and thus polling is necessary.
 - (void)checkMouseInRect {
   NSPoint point = [NSEvent mouseLocation];
   point = [[self window] convertScreenToBase:point];
   point = [self convertPoint:point fromView:nil];
   if (!NSPointInRect(point, [self insetBounds])) {
     [self doHighlight:NO];
   }
 }
 
 // Returns the bounds of the receiver slightly inset to avoid highlighting both
 // buttons in a pair that overlap.
 - (NSRect)insetBounds {
   return NSInsetRect([self bounds], 2, 1);
 }
 
-- (BOOL)shouldHighlightOnHover {
-  // There's a cell drawing bug in 10.5 that was fixed on 10.6.  Hover states
-  // look terrible due to this, so disable highlighting on 10.5.
-  return base::mac::IsOSSnowLeopardOrLater();
-}
-
 @end