Add missing (and remove superfluous) 'explicit' from constructors.

chrome/browser/ui/cocoa/tabs/tab_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_controller.h"
 
 #include <cmath>
 
 #include "base/mac/bundle_locations.h"
 #include "base/mac/mac_util.h"
@@ skipping 18 matching lines @@
 @synthesize target = target_;
 @synthesize url = url_;
 
 namespace TabControllerInternal {
 
 // A C++ delegate that handles enabling/disabling menu items and handling when
 // a menu command is chosen. Also fixes up the menu item label for "pin/unpin
 // tab".
 class MenuDelegate : public ui::SimpleMenuModel::Delegate {
  public:
-  explicit MenuDelegate(id<TabControllerTarget> target, TabController* owner)
+  MenuDelegate(id<TabControllerTarget> target, TabController* owner)
       : target_(target),
         owner_(owner) {}
 
   // Overridden from ui::SimpleMenuModel::Delegate
   virtual bool IsCommandIdChecked(int command_id) const { return false; }
   virtual bool IsCommandIdEnabled(int command_id) const {
     TabStripModel::ContextMenuCommand command =
         static_cast<TabStripModel::ContextMenuCommand>(command_id);
     return [target_ isCommandEnabled:command forController:owner_];
   }
@@ skipping 333 matching lines @@
 // TabStripDragController.
 - (BOOL)tabCanBeDragged:(TabController*)controller {
   return [[target_ dragController] tabCanBeDragged:controller];
 }
 
 - (void)maybeStartDrag:(NSEvent*)event forTab:(TabController*)tab {
   [[target_ dragController] maybeStartDrag:event forTab:tab];
 }
 
 @end