Ensure ShellExtensionSystem::Init() is called in all extensions_browsertests.

extensions/browser/guest_view/app_view/app_view_apitest.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 "base/command_line.h"
 #include "base/path_service.h"
 #include "base/strings/stringprintf.h"
 #include "components/guest_view/browser/guest_view_manager.h"
 #include "components/guest_view/browser/guest_view_manager_factory.h"
 #include "components/guest_view/browser/test_guest_view_manager.h"
@@ skipping 102 matching lines @@
   const Extension* LoadApp(const std::string& app_location) {
     base::FilePath test_data_dir;
     PathService::Get(DIR_TEST_DATA, &test_data_dir);
     test_data_dir = test_data_dir.AppendASCII(app_location.c_str());
     return extension_system_->LoadApp(test_data_dir);
   }
 
   void RunTest(const std::string& test_name,
                const std::string& app_location,
                const std::string& app_to_embed) {
-    extension_system_->Init();
-
     const Extension* app_embedder = LoadApp(app_location);
     ASSERT_TRUE(app_embedder);
     const Extension* app_embedded = LoadApp(app_to_embed);
     ASSERT_TRUE(app_embedded);
 
     extension_system_->LaunchApp(app_embedder->id());
 
     ExtensionTestMessageListener launch_listener("LAUNCHED", false);
     ASSERT_TRUE(launch_listener.WaitUntilSatisfied());
 
@@ skipping 68 matching lines @@
 #endif
 // Tests that <appview> is able to navigate to another installed app.
 IN_PROC_BROWSER_TEST_P(AppViewTest,
                        MAYBE_TestAppViewWithUndefinedDataShouldSucceed) {
   RunTest("testAppViewWithUndefinedDataShouldSucceed",
           "app_view/apitest",
           "app_view/apitest/skeleton");
 }
 
 }  // namespace extensions