Enable tab scrubbing by default

chrome/browser/ui/views/ash/tab_scrubber_browsertest.cc

 // 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.
 
 #include "chrome/browser/ui/views/ash/tab_scrubber.h"
 
 #include "ash/display/event_transformation_handler.h"
 #include "ash/shell.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 22 matching lines @@
                         public TabStripModelObserver {
  public:
   TabScrubberTest()
       : target_index_(-1) {
   }
 
   virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
 #if defined(OS_CHROMEOS)
     command_line->AppendSwitch(switches::kNaturalScrollDefault);
 #endif
-    command_line->AppendSwitch(switches::kAshEnableTabScrubbing);
     command_line->AppendSwitch(switches::kOpenAsh);
   }
 
   virtual void SetUpOnMainThread() OVERRIDE {
     TabScrubber::GetInstance()->set_activation_delay(
         base::TimeDelta::FromMilliseconds(0));
 
     // Disable external monitor scaling of coordinates.
     ash::Shell* shell = ash::Shell::GetInstance();
     shell->event_transformation_handler()->set_transformation_mode(
@@ skipping 345 matching lines @@
 IN_PROC_BROWSER_TEST_F(TabScrubberTest, MoveAfter) {
   AddTabs(browser(), 2);
 
   SendScrubEvent(browser(), 1);
   EXPECT_TRUE(TabScrubber::GetInstance()->IsActivationPending());
   browser()->tab_strip_model()->MoveSelectedTabsTo(0);
   EXPECT_EQ(2, TabScrubber::GetInstance()->highlighted_tab());
 }
 
 #endif // OS_CHROMEOS