Change other usages of .size() to .empty() when applicable.

chrome/browser/sync/profile_sync_service.cc

 // Copyright (c) 2011 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/sync/profile_sync_service.h"
 
 #include <map>
 #include <set>
 
 #include "base/basictypes.h"
@@ skipping 415 matching lines @@
                        credentials,
                        delete_sync_data_folder,
                        notifier_options_);
 }
 
 void ProfileSyncService::CreateBackend() {
   backend_.reset(new SyncBackendHost(profile_));
 }
 
 bool ProfileSyncService::IsEncryptedDatatypeEnabled() const {
-  return encrypted_types_.size() > 0;
+  return !encrypted_types_.empty();
 }
 
 void ProfileSyncService::StartUp() {
   // Don't start up multiple times.
   if (backend_.get()) {
     VLOG(1) << "Skipping bringing up backend host.";
     return;
   }
 
   DCHECK(AreCredentialsAvailable());
@@ skipping 901 matching lines @@
   // is initialized, all enabled data types are consistent with one
   // another, and no unrecoverable error has transpired.
   if (unrecoverable_error_detected_)
     return false;
 
   if (!data_type_manager_.get())
     return false;
 
   return data_type_manager_->state() == DataTypeManager::CONFIGURED;
 }