[iOS] Upstream FirstRun configuration and metrics

ios/chrome/browser/first_run/first_run.mm

 // Copyright 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 "ios/chrome/browser/first_run/first_run.h"
 
-#import <Foundation/Foundation.h>
-
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/path_service.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "ios/chrome/browser/chrome_paths.h"
 
 namespace {
 
 // The absence of kSentinelFile file will tell us it is a first run.
-const char kSentinelFile[] = "First Run";
+const base::FilePath::CharType kSentinelFile[] = FILE_PATH_LITERAL("First Run");
 
 // RLZ ping delay pref name.
 const char kPingDelayPrefName[] = "distribution.ping_delay";
 
 }  // namespace
 
 FirstRun::FirstRunState FirstRun::first_run_ = FIRST_RUN_UNKNOWN;
 
 // static
 bool FirstRun::GetFirstRunSentinelFilePath(base::FilePath* path) {
   base::FilePath first_run_sentinel;
   if (!PathService::Get(ios::DIR_USER_DATA, &first_run_sentinel))
     return false;
-  *path = first_run_sentinel.AppendASCII(kSentinelFile);
+  *path = first_run_sentinel.Append(kSentinelFile);
   return true;
 }
 
 // static
 bool FirstRun::IsChromeFirstRun() {
   if (first_run_ != FIRST_RUN_UNKNOWN)
     return first_run_ == FIRST_RUN_TRUE;
 
   base::FilePath first_run_sentinel;
   if (!GetFirstRunSentinelFilePath(&first_run_sentinel) ||
@@ skipping 25 matching lines @@
 // static
 const char* FirstRun::GetPingDelayPrefName() {
   return kPingDelayPrefName;
 }
 
 // static
 void FirstRun::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* registry) {
   registry->RegisterIntegerPref(GetPingDelayPrefName(), 0);
 }