Consolidate manifest handler registration.

chrome/common/extensions/manifest_tests/extension_manifests_isolatedapp_unittest.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/common/extensions/manifest_tests/extension_manifest_test.h"
 
 #include "base/command_line.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_manifest_constants.h"
 #include "chrome/common/extensions/manifest_handlers/app_isolation_info.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace errors = extension_manifest_errors;
 
 namespace extensions {
 
 class IsolatedAppsManifestTest : public ExtensionManifestTest {
- protected:
-  virtual void SetUp() OVERRIDE {
-    testing::Test::SetUp();
-    (new AppIsolationHandler)->Register();
-  }
 };
 
 TEST_F(IsolatedAppsManifestTest, IsolatedApps) {
   // Requires --enable-experimental-extension-apis
   LoadAndExpectError("isolated_app_valid.json",
                      errors::kExperimentalFlagRequired);
 
   CommandLine::ForCurrentProcess()->AppendSwitch(
       switches::kEnableExperimentalExtensionApis);
   scoped_refptr<Extension> extension2(
       LoadAndExpectSuccess("isolated_app_valid.json"));
   EXPECT_TRUE(AppIsolationInfo::HasIsolatedStorage(extension2));
 }
 
 }  // namespace extensions