[Mac] Respect natural/inverted scroll direction on Lion when gesturing.

chrome/browser/ui/cocoa/browser_window_controller_private.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/browser_window_controller_private.h"
 
 #include "base/command_line.h"
 #include "base/mac/mac_util.h"
 #import "base/memory/scoped_nsobject.h"
 #include "chrome/browser/browser_process.h"
@@ skipping 550 matching lines @@
   // The three-finger gesture is controlled by the integer preference
   // |com.apple.trackpad.threeFingerHorizSwipeGesture|. Its value is 0 for (A)
   // and 1 for (B, C).
   //
   // The two-finger gesture is controlled by the preference below and is boolean
   // YES for (A, C) and NO for (B).
   NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];
   return [defaults boolForKey:@"AppleEnableSwipeNavigateWithScrolls"];
 }
 
+- (BOOL)isScrollDirectionInverted {

[Nico, 2011/07/26 15:00:18]

Can you move this and the previous function to somewhere else? Chances are we'll
need this somewhere else as well, and it keeps this file smaller.

[Robert Sesek, 2011/07/26 15:56:05]

Done.

+  if (!base::mac::IsOSLionOrLater())
+    return NO;
+
+  NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];
+  // The defaults must be synchronized here otherwise a stale value will be
+  // returned for an indeterminante amount of time. For some reason, this is
+  // not necessary in |-recognizeTwoFingerGestures|.
+  [defaults synchronize];
+  return [defaults boolForKey:@"com.apple.swipescrolldirection"];
+}
+
 @end  // @implementation BrowserWindowController(Private)