PlatformAppApiTest class should not enable experimental APIs by default

chrome/browser/extensions/api/serial/serial_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 <deque>
 #include <string>
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/extensions/api/serial/serial_api.h"
 #include "chrome/browser/extensions/api/serial/serial_connection.h"
 #include "chrome/browser/extensions/extension_apitest.h"
 #include "chrome/browser/extensions/extension_function.h"
 #include "chrome/browser/extensions/extension_function_test_utils.h"
 #include "chrome/browser/extensions/extension_test_message_listener.h"
 #include "chrome/browser/ui/browser.h"
 #include "content/public/browser/browser_thread.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
 using testing::_;
 using testing::Return;
 
 using content::BrowserThread;
 
 namespace {
 
-class SerialApiTest : public PlatformAppApiTest {
+class SerialApiTest : public ExtensionApiTest {
  public:
   SerialApiTest() {}
 };
 
 }  // namespace
 
 namespace extensions {
 
 class FakeSerialGetPortsFunction : public AsyncExtensionFunction {
  public:
@@ skipping 142 matching lines @@
 
   ASSERT_TRUE(RunExtensionTest("serial/api")) << message_;
 }
 
 IN_PROC_BROWSER_TEST_F(SerialApiTest, SerialRealHardware) {
   ResultCatcher catcher;
   catcher.RestrictToProfile(browser()->profile());
 
   ASSERT_TRUE(RunExtensionTest("serial/real_hardware")) << message_;
 }