[Sync] Rename syncable_prefs to sync_preferences.

ios/chrome/browser/sync/BUILD.gn

 # Copyright 2016 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.
 
 source_set("sync") {
   sources = [
     "ios_chrome_profile_sync_service_factory.cc",
     "ios_chrome_profile_sync_service_factory.h",
     "ios_chrome_sync_client.h",
     "ios_chrome_sync_client.mm",
@@ skipping 16 matching lines @@
     "//components/keyed_service/core",
     "//components/keyed_service/ios",
     "//components/network_time",
     "//components/password_manager/core/browser",
     "//components/password_manager/sync/browser",
     "//components/prefs",
     "//components/search_engines",
     "//components/sessions",
     "//components/signin/core/browser",
     "//components/sync",
+    "//components/sync_preferences",
     "//components/sync_sessions",
-    "//components/syncable_prefs",
     "//google_apis",
     "//ios/chrome/browser:browser_no_public_deps",
     "//ios/chrome/browser/autofill",
     "//ios/chrome/browser/bookmarks",
     "//ios/chrome/browser/browser_state",
     "//ios/chrome/browser/dom_distiller",
     "//ios/chrome/browser/favicon",
     "//ios/chrome/browser/history",
     "//ios/chrome/browser/invalidation",
     "//ios/chrome/browser/passwords",
@@ skipping 40 matching lines @@
     "//components/signin/core/browser",
     "//components/sync",
     "//components/sync:test_support_driver",
     "//ios/chrome/browser/browser_state",
     "//ios/chrome/browser/signin",
     "//ios/chrome/common",
     "//ios/web",
     "//testing/gmock",
   ]
 }