Fix ExtensionServiceTest.ClearExtensionData flakiness

chrome/browser/extensions/extension_browsertest.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/browser/extensions/extension_browsertest.h"
 
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/file_util.h"
@@ skipping 534 matching lines @@
 void ExtensionBrowserTest::UnloadExtension(const std::string& extension_id) {
   ExtensionService* service = extensions::ExtensionSystem::Get(
       profile())->extension_service();
   service->UnloadExtension(extension_id,
                            extensions::UnloadedExtensionInfo::REASON_DISABLE);
 }
 
 void ExtensionBrowserTest::UninstallExtension(const std::string& extension_id) {
   ExtensionService* service = extensions::ExtensionSystem::Get(
       profile())->extension_service();
-  service->UninstallExtension(
-      extension_id, extensions::UNINSTALL_REASON_FOR_TESTING, NULL);
+  service->UninstallExtension(extension_id,
+                              extensions::UNINSTALL_REASON_FOR_TESTING,
+                              base::Bind(&base::DoNothing),
+                              NULL);
 }
 
 void ExtensionBrowserTest::DisableExtension(const std::string& extension_id) {
   ExtensionService* service = extensions::ExtensionSystem::Get(
       profile())->extension_service();
   service->DisableExtension(extension_id, Extension::DISABLE_USER_ACTION);
 }
 
 void ExtensionBrowserTest::EnableExtension(const std::string& extension_id) {
   ExtensionService* service = extensions::ExtensionSystem::Get(
@@ skipping 76 matching lines @@
   return extensions::browsertest_util::ExecuteScriptInBackgroundPage(
       profile(), extension_id, script);
 }
 
 bool ExtensionBrowserTest::ExecuteScriptInBackgroundPageNoWait(
     const std::string& extension_id,
     const std::string& script) {
   return extensions::browsertest_util::ExecuteScriptInBackgroundPageNoWait(
       profile(), extension_id, script);
 }