[Cleanup] Clean up Easy Unlock code a bit.

chrome/browser/signin/easy_unlock_service_signin_chromeos.cc

 // Copyright 2014 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/signin/easy_unlock_service_signin_chromeos.h"
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
@@ skipping 266 matching lines @@
     return;
   service_active_ = false;
 
   weak_ptr_factory_.InvalidateWeakPtrs();
   ScreenlockBridge::Get()->RemoveObserver(this);
   chromeos::LoginState::Get()->RemoveObserver(this);
   STLDeleteContainerPairSecondPointers(user_data_.begin(), user_data_.end());
   user_data_.clear();
 }
 
-bool EasyUnlockServiceSignin::IsAllowedInternal() {
+bool EasyUnlockServiceSignin::IsAllowedInternal() const {
   return service_active_ &&
          !user_id_.empty() &&
          !chromeos::LoginState::Get()->IsUserLoggedIn();
 }
 
 void EasyUnlockServiceSignin::OnScreenDidLock() {
   // Update initial UI is when the account picker on login screen is ready.
   ShowInitialUserState();
 }
 
@@ skipping 90 matching lines @@
     return NULL;
 
   std::map<std::string, UserData*>::const_iterator it =
       user_data_.find(user_id_);
   if (it == user_data_.end())
     return NULL;
   if (it->second->state != USER_DATA_STATE_LOADED)
     return NULL;
   return it->second;
 }