mac: Remove IsOSLion().

chrome/browser/ui/cocoa/tabs/tab_strip_controller.mm

 // Copyright (c) 2012 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/tabs/tab_strip_controller.h"
 
 #import <QuartzCore/QuartzCore.h>
 
 #include <cmath>
 #include <limits>
@@ skipping 1113 matching lines @@
     NSValue* oldTargetValue = [targetFrames_ objectForKey:identifier];
     if (!oldTargetValue ||
         !NSEqualRects([oldTargetValue rectValue], tabFrame)) {
       // Redraw the tab once it moves to its final location. Because we're
       // using Core Animation, each tab caches its contents until told to
       // redraw. Without forcing a redraw at the end of the move, tabs will
       // display the wrong content when using a theme that creates transparent
       // tabs.
       ScopedNSAnimationContextGroup subAnimationGroup(animate);
       subAnimationGroup.SetCurrentContextDuration(kAnimationDuration);
-      // -[NSAnimationContext setCompletionHandler:] is only available on
-      // 10.7 and higher.
-      if (base::mac::IsOSLionOrLater()) {
-        NSView* tabView = [tab view];
-        [[NSAnimationContext currentContext] setCompletionHandler:^{
-          [tabView setNeedsDisplay:YES];
-        }];
-      }
+      NSView* tabView = [tab view];
+      [[NSAnimationContext currentContext] setCompletionHandler:^{
+        [tabView setNeedsDisplay:YES];
+      }];
 
       [frameTarget setFrame:tabFrame];
       [targetFrames_ setObject:[NSValue valueWithRect:tabFrame]
                         forKey:identifier];
     }
 
     enclosingRect = NSUnionRect(tabFrame, enclosingRect);
 
     offset += NSWidth(tabFrame);
     offset -= kTabOverlap;
@@ skipping 1141 matching lines @@
 
 - (TabAlertState)alertStateForContents:(content::WebContents*)contents {
   return chrome::GetTabAlertStateForContents(contents);
 }
 
 - (void)themeDidChangeNotification:(NSNotification*)notification {
   [newTabButton_ setImages];
 }
 
 @end