remove rollback to xmpp when GCM disabled

chrome/browser/invalidation/ticl_profile_settings_provider.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/invalidation/ticl_profile_settings_provider.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/prefs/pref_service.h"
@@ skipping 15 matching lines @@
   registrar_.Add(
       gcm::prefs::kGCMChannelStatus,
       base::Bind(&TiclProfileSettingsProvider::FireOnUseGCMChannelChanged,
                  base::Unretained(this)));
 }
 
 TiclProfileSettingsProvider::~TiclProfileSettingsProvider() {
 }
 
 bool TiclProfileSettingsProvider::UseGCMChannel() const {
-  if (!gcm::GCMProfileService::IsGCMEnabled(profile_)) {
-    // Do not try to use GCM channel if GCM is disabled.
-    return false;
-  }
-
   if (profile_->GetPrefs()->GetBoolean(
           prefs::kInvalidationServiceUseGCMChannel)) {
     // Use GCM channel if it was enabled via prefs.
     return true;
   }
 
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kInvalidationUseGCMChannel)) {
     // Use GCM channel if it was enabled via a command-line switch.
     return true;
   }
 
   // By default, do not use GCM channel.
   return false;
 }
 
 }  // namespace invalidation