[iOS] Remove support for asynchronous pref creation

Review URL: https://codereview.chromium.org/1467143002

Cr-Commit-Position: refs/heads/master@{#361093}

ios/chrome/browser/application_context_impl.cc

@@ -198,7 +198,7 @@ void ApplicationContextImpl::CreateLocalState() {
   RegisterLocalStatePrefs(pref_registry.get());
 
   local_state_ = ::CreateLocalState(
-      local_state_path, local_state_task_runner_.get(), pref_registry, false);
+      local_state_path, local_state_task_runner_.get(), pref_registry);
 
   const int max_per_proxy =
       local_state_->GetInteger(ios::prefs::kMaxConnectionsPerProxy);

ios/chrome/browser/prefs/ios_chrome_pref_service_factory.cc

@@ -33,12 +33,10 @@ void HandleReadError(PersistentPrefStore::PrefReadError error) {
 
 void PrepareFactory(syncable_prefs::PrefServiceSyncableFactory* factory,
                     const base::FilePath& pref_filename,
-                    base::SequencedTaskRunner* pref_io_task_runner,
-                    bool async) {
+                    base::SequencedTaskRunner* pref_io_task_runner) {
   factory->set_user_prefs(make_scoped_refptr(new JsonPrefStore(
       pref_filename, pref_io_task_runner, scoped_ptr<PrefFilter>())));
 
-  factory->set_async(async);
   factory->set_read_error_callback(base::Bind(&HandleReadError));
   factory->SetPrefModelAssociatorClient(
       IOSChromePrefModelAssociatorClient::GetInstance());
@@ -49,10 +47,9 @@ void PrepareFactory(syncable_prefs::PrefServiceSyncableFactory* factory,
 scoped_ptr<PrefService> CreateLocalState(
     const base::FilePath& pref_filename,
     base::SequencedTaskRunner* pref_io_task_runner,
-    const scoped_refptr<PrefRegistry>& pref_registry,
-    bool async) {
+    const scoped_refptr<PrefRegistry>& pref_registry) {
   syncable_prefs::PrefServiceSyncableFactory factory;
-  PrepareFactory(&factory, pref_filename, pref_io_task_runner, async);
+  PrepareFactory(&factory, pref_filename, pref_io_task_runner);
   return factory.Create(pref_registry.get());
 }
 
@@ -60,8 +57,7 @@ scoped_ptr<syncable_prefs::PrefServiceSyncable> CreateBrowserStatePrefs(
     const base::FilePath& browser_state_path,
     base::SequencedTaskRunner* pref_io_task_runner,
     TrackedPreferenceValidationDelegate* validation_delegate,
-    const scoped_refptr<user_prefs::PrefRegistrySyncable>& pref_registry,
-    bool async) {
+    const scoped_refptr<user_prefs::PrefRegistrySyncable>& pref_registry) {
   // chrome_prefs::CreateProfilePrefs uses ProfilePrefStoreManager to create
   // the preference store however since Chrome on iOS does not need to track
   // preference modifications (as applications are sand-boxed), it can use a
@@ -69,7 +65,7 @@ scoped_ptr<syncable_prefs::PrefServiceSyncable> CreateBrowserStatePrefs(
   // on platforms that do not track preference modifications).
   syncable_prefs::PrefServiceSyncableFactory factory;
   PrepareFactory(&factory, browser_state_path.Append(kPreferencesFilename),
-                 pref_io_task_runner, async);
+                 pref_io_task_runner);
   scoped_ptr<syncable_prefs::PrefServiceSyncable> pref_service =
       factory.CreateSyncable(pref_registry.get());
   ConfigureDefaultSearchPrefMigrationToDictionaryValue(pref_service.get());

ios/chrome/browser/prefs/ios_chrome_pref_service_factory.h

@@ -34,19 +34,17 @@ class PrefRegistrySyncable;
 // for Chrome on iOS with the applicable PrefStores. The |pref_filename| points
 // to the user preference file. This is the usual way to create a new
 // PrefService. |pref_registry| keeps the list of registered prefs and their
-// default valuers. If |async| is true, asynchronous version is used.
+// default values.
 scoped_ptr<PrefService> CreateLocalState(
     const base::FilePath& pref_filename,
     base::SequencedTaskRunner* pref_io_task_runner,
-    const scoped_refptr<PrefRegistry>& pref_registry,
-    bool async);
+    const scoped_refptr<PrefRegistry>& pref_registry);
 
 scoped_ptr<syncable_prefs::PrefServiceSyncable> CreateBrowserStatePrefs(
     const base::FilePath& browser_state_path,
     base::SequencedTaskRunner* pref_io_task_runner,
     TrackedPreferenceValidationDelegate* validation_delegate,
-    const scoped_refptr<user_prefs::PrefRegistrySyncable>& pref_registry,
-    bool async);
+    const scoped_refptr<user_prefs::PrefRegistrySyncable>& pref_registry);
 
 // Creates an incognito copy of |pref_service| that shares most prefs but uses
 // a fresh non-persistent overlay for the user pref store.