Move scoped_temp_dir from base to base/files

chrome/browser/extensions/api/file_system/file_system_apitest.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 "base/file_util.h"
 #include "base/path_service.h"
 #include "chrome/browser/extensions/api/file_system/file_system_api.h"
 #include "chrome/browser/extensions/platform_app_browsertest_util.h"
 
 using extensions::FileSystemChooseEntryFunction;
@@ skipping 19 matching lines @@
     }
     FilePath destination = temp_dir_.path().AppendASCII(destination_name);
     if (copy_gold) {
       FilePath source = test_root_folder_.AppendASCII("gold.txt");
       EXPECT_TRUE(file_util::CopyFile(source, destination));
     }
     return destination;
   }
 
   FilePath test_root_folder_;
-  ScopedTempDir temp_dir_;
+  base::ScopedTempDir temp_dir_;
 };
 
 IN_PROC_BROWSER_TEST_F(FileSystemApiTest, FileSystemApiGetDisplayPath) {
   FilePath test_file = test_root_folder_.AppendASCII("gold.txt");
   FileSystemChooseEntryFunction::SkipPickerAndAlwaysSelectPathForTest(
       &test_file);
   ASSERT_TRUE(RunPlatformAppTest("api_test/file_system/get_display_path"))
       << message_;
 }
 
@@ skipping 162 matching lines @@
 }
 
 IN_PROC_BROWSER_TEST_F(FileSystemApiTest, FileSystemApiIsWritableTest) {
   FilePath test_file = TempFilePath("writable.txt", true);
   ASSERT_FALSE(test_file.empty());
   FileSystemChooseEntryFunction::SkipPickerAndAlwaysSelectPathForTest(
       &test_file);
   ASSERT_TRUE(RunPlatformAppTest(
       "api_test/file_system/is_writable_file_entry")) << message_;
 }