Fix build error with gcc 4.9.3

chrome/browser/password_manager/native_backend_kwallet_x.cc

 // Copyright (c) 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 "chrome/browser/password_manager/native_backend_kwallet_x.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <map>
@@ skipping 370 matching lines @@
   // Get the wallet name.
   error = kwallet_dbus_.NetworkWallet(&wallet_name_);
   switch (error) {
     case KWalletDBus::Error::CANNOT_CONTACT:
       return TEMPORARY_FAIL;
     case KWalletDBus::Error::CANNOT_READ:
       return PERMANENT_FAIL;
     case KWalletDBus::Error::SUCCESS:
       return INIT_SUCCESS;
   }
+
+  NOTREACHED();
+  return PERMANENT_FAIL;
 }
 
 password_manager::PasswordStoreChangeList NativeBackendKWallet::AddLogin(
     const PasswordForm& form) {
   int wallet_handle = WalletHandle();
   if (wallet_handle == kInvalidKWalletHandle)
     return password_manager::PasswordStoreChangeList();
 
   ScopedVector<autofill::PasswordForm> forms;
   if (!GetLoginsList(form.signon_realm, wallet_handle, &forms))
@@ skipping 422 matching lines @@
   }
 
   return handle;
 }
 
 std::string NativeBackendKWallet::GetProfileSpecificFolderName() const {
   // Originally, the folder name was always just "Chrome Form Data".
   // Now we use it to distinguish passwords for different profiles.
   return base::StringPrintf("%s (%d)", kKWalletFolder, profile_id_);
 }