sync: Add --enable-sync-sessions-v2 and necessary plumbing to use SessionsSyncManager.

chrome/browser/prerender/prerender_field_trial.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/prerender/prerender_field_trial.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
@@ skipping 302 matching lines @@
     SplitStringUsingSubstr(elements[i], "=", &key_value);
     if (key_value.size() == 2 && key_value[0] == spec_key)
       return key_value[1];
   }
   return string();
 }
 
 bool IsUnencryptedSyncEnabled(Profile* profile) {
   ProfileSyncService* service = ProfileSyncServiceFactory::GetInstance()->
       GetForProfile(profile);
-  return service && service->GetSessionModelAssociator() &&
+  return service && service->GetOpenTabsUIDelegate() &&
       !service->EncryptEverythingEnabled();
 }
 
 // Indicates whether the Local Predictor is enabled based on field trial
 // selection.
 bool IsLocalPredictorEnabled() {
 #if defined(OS_ANDROID) || defined(OS_IOS)
   return false;
 #endif
   if (CommandLine::ForCurrentProcess()->HasSwitch(
@@ skipping 136 matching lines @@
   return GetLocalPredictorSpecValue(kSkipPrerenderLocalCanadidates) ==
       kEnabledGroup;
 }
 
 bool SkipLocalPredictorServiceCandidates() {
   return GetLocalPredictorSpecValue(kSkipPrerenderServiceCanadidates) ==
       kEnabledGroup;
 }
 
 }  // namespace prerender