Make MockExtensionSystemFactory available in all ExtensionsTests.

extensions/browser/api_unittest.cc

 // Copyright 2014 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 "extensions/browser/api_unittest.h"
 
 #include "base/values.h"
 #include "components/user_prefs/user_prefs.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
@@ skipping 14 matching lines @@
 #include "extensions/common/manifest.h"
 #include "extensions/common/manifest_handlers/background_info.h"
 #include "extensions/common/value_builder.h"
 
 namespace utils = extensions::api_test_utils;
 
 namespace extensions {
 
 ApiUnitTest::ApiUnitTest()
     : notification_service_(content::NotificationService::Create()) {
-  extensions_browser_client()->set_extension_system_factory(
-      &extension_system_factory_);
 }
 
 ApiUnitTest::~ApiUnitTest() {
 }
 
 void ApiUnitTest::SetUp() {
   ExtensionsTest::SetUp();
 
   thread_bundle_.reset(new content::TestBrowserThreadBundle(
       content::TestBrowserThreadBundle::DEFAULT));
@@ skipping 66 matching lines @@
     function->SetRenderViewHost(contents_->GetRenderViewHost());
   return utils::RunFunctionAndReturnError(function, args, browser_context());
 }
 
 void ApiUnitTest::RunFunction(UIThreadExtensionFunction* function,
                               const std::string& args) {
   RunFunctionAndReturnValue(function, args);
 }
 
 }  // namespace extensions