Move crypto_helpers from sync to base

chrome/browser/password_manager/encryptor_password_mac.mm

 // 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/password_manager/encryptor_password_mac.h"
 
 #import <Security/Security.h>
 
 #include "chrome/browser/keychain_mac.h"
-#include "chrome/browser/sync/util/crypto_helpers.h"
+#include "chrome/common/random.h"
 #include "ui/base/l10n/l10n_util.h"
 
 namespace {
 
 // Generates a random password and adds it to the Keychain.  The added password
 // is returned from the function.  If an error occurs, an empty password is
 // returned.
 std::string AddRandomPasswordToKeychain(const MacKeychain& keychain,
                                         const std::string& service_name,
                                         const std::string& account_name) {
-  std::string password = Generate128BitRandomHexString();
+  std::string password = Generate128BitRandomBase64String();
   void* password_data =
       const_cast<void*>(static_cast<const void*>(password.data()));
 
   OSStatus error = keychain.AddGenericPassword(NULL,
                                                service_name.size(),
                                                service_name.data(),
                                                account_name.size(),
                                                account_name.data(),
                                                password.size(),
                                                password_data,
@@ skipping 34 matching lines @@
     return password;
   } else if (error == errSecItemNotFound) {
     return AddRandomPasswordToKeychain(keychain_, service_name, account_name);
   } else {
     DLOG(ERROR) << "Keychain lookup failed with error " << error;
     return std::string();
   }
 }