[Sync] Rename syncable_prefs to sync_preferences.

ios/chrome/browser/prefs/ios_chrome_pref_model_associator_client.h

 // Copyright 2015 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.
 
 #ifndef IOS_CHROME_BROWSER_PREFS_IOS_CHROME_PREF_MODEL_ASSOCIATOR_CLIENT_H_
 #define IOS_CHROME_BROWSER_PREFS_IOS_CHROME_PREF_MODEL_ASSOCIATOR_CLIENT_H_
 
 #include <string>
 
 #include "base/macros.h"
-#include "components/syncable_prefs/pref_model_associator_client.h"
+#include "components/sync_preferences/pref_model_associator_client.h"
 
 namespace base {
 template <typename T>
 struct DefaultSingletonTraits;
 }
 
 class IOSChromePrefModelAssociatorClient
-    : public syncable_prefs::PrefModelAssociatorClient {
+    : public sync_preferences::PrefModelAssociatorClient {
  public:
   // Returns the global instance.
   static IOSChromePrefModelAssociatorClient* GetInstance();
 
  private:
   friend struct base::DefaultSingletonTraits<
       IOSChromePrefModelAssociatorClient>;
 
   IOSChromePrefModelAssociatorClient();
   ~IOSChromePrefModelAssociatorClient() override;
 
-  // syncable_prefs::PrefModelAssociatorClient implementation.
+  // sync_preferences::PrefModelAssociatorClient implementation.
   bool IsMergeableListPreference(const std::string& pref_name) const override;
   bool IsMergeableDictionaryPreference(
       const std::string& pref_name) const override;
 
   DISALLOW_COPY_AND_ASSIGN(IOSChromePrefModelAssociatorClient);
 };
 
 #endif  // IOS_CHROME_BROWSER_PREFS_IOS_CHROME_PREF_MODEL_ASSOCIATOR_CLIENT_H_