Removing iPad Tab Switcher experimental flag.

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

 // Copyright 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 "ios/chrome/browser/ui/tabs/tab_strip_controller.h"
 #import "ios/chrome/browser/ui/tabs/tab_strip_controller_private.h"
 
 #include <cmath>
 #include <vector>
 
@@ skipping 104 matching lines @@
 }
 
 @interface TabStripController ()<TabModelObserver,
                                  TabStripViewLayoutDelegate,
                                  UIGestureRecognizerDelegate,
                                  UIScrollViewDelegate> {
   base::scoped_nsobject<TabModel> _tabModel;
   UIView* _view;
   TabStripView* _tabStripView;
   UIButton* _buttonNewTab;
+  // TODO(crbug.com/687132): Remove toggle button.
   UIButton* _modeToggleButton;         // weak, nil if not visible.
   UIButton* _tabSwitcherToggleButton;  // weak, nil if not visible.
 
   // Background view of the toggle button. Only visible while in compact layout.
   base::scoped_nsobject<UIImageView> _toggleButtonBackgroundView;
 
   TabStrip::Style _style;
   base::WeakNSProtocol<id<FullScreenControllerDelegate>> _fullscreenDelegate;
 
   // Array of TabViews.  There is a one-to-one correspondence between this array
@@ skipping 949 matching lines @@
   _modeToggleButton = [UIButton buttonWithType:UIButtonTypeCustom];
   _modeToggleButton.frame = buttonFrame;
   [_modeToggleButton setImageEdgeInsets:UIEdgeInsetsMake(7, 5, 7, 5)];
   _modeToggleButton.autoresizingMask = UIViewAutoresizingFlexibleLeftMargin;
   _modeToggleButton.backgroundColor = [UIColor clearColor];
   [_modeToggleButton setImage:toggleIcon forState:UIControlStateNormal];
   // Set target/action to bubble up with command id as tag.
   [_modeToggleButton addTarget:nil
                         action:@selector(chromeExecuteCommand:)
               forControlEvents:UIControlEventTouchUpInside];
-  [_modeToggleButton setTag:IDC_SWITCH_BROWSER_MODES];

[rohitrao (ping after 24h), 2017/02/01 18:34:34]

Can this constant can be deleted from
ios/chrome/browser/ui/commands/ios_command_ids.h now?

[jif, 2017/02/03 12:55:51]

It's still used in the tab_strip_controller, so I'd rather do it in the
CL that does the clean up of the tab_strip_controller.
See CL description.

   [_modeToggleButton addTarget:self
                         action:@selector(recordUserMetrics:)
               forControlEvents:UIControlEventTouchUpInside];
 
   SetA11yLabelAndUiAutomationName(_modeToggleButton,
                                   toggleIdsAccessibilityLabel,
                                   toggleEnglishUiAutomationName);
   [_view addSubview:_modeToggleButton];
   // Shrink the scroll view.
   [self updateScrollViewFrameForToggleButton];
@@ skipping 617 matching lines @@
 
 @implementation TabStripController (Testing)
 
 - (TabView*)existingTabViewForTab:(Tab*)tab {
   NSUInteger tabIndex = [_tabModel indexOfTab:tab];
   NSUInteger tabViewIndex = [self indexForModelIndex:tabIndex];
   return [_tabArray objectAtIndex:tabViewIndex];
 }
 
 @end