Ensure tests have an active task runner

chrome/browser/download/download_target_determiner_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 "base/at_exit.h"
 #include "base/files/file_path.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/message_loop/message_loop.h"
 #include "base/observer_list.h"
 #include "base/prefs/pref_service.h"
@@ skipping 1997 matching lines @@
 // needs to disable plugin discovery and we need to use a
 // ShadowingAtExitManager to discard the tainted PluginService. Unfortunately,
 // PluginService carries global state.
 class DownloadTargetDeterminerTestWithPlugin
     : public DownloadTargetDeterminerTest {
  public:
   DownloadTargetDeterminerTestWithPlugin()
       : old_plugin_service_filter_(NULL) {}
 
   void SetUp() override {
+    DownloadTargetDeterminerTest::SetUp();
     content::PluginService* plugin_service =
         content::PluginService::GetInstance();
     plugin_service->Init();
     plugin_service->DisablePluginsDiscoveryForTesting();
     old_plugin_service_filter_ = plugin_service->GetFilter();
     plugin_service->SetFilter(&mock_plugin_filter_);
-    DownloadTargetDeterminerTest::SetUp();
   }
 
   void TearDown() override {
     content::PluginService::GetInstance()->SetFilter(
         old_plugin_service_filter_);
     DownloadTargetDeterminerTest::TearDown();
   }
 
  protected:
   content::PluginServiceFilter* old_plugin_service_filter_;
@@ skipping 201 matching lines @@
   EXPECT_CALL(mock_plugin_filter_, MockPluginAvailable(npapi_plugin.path()))
       .WillRepeatedly(Return(true));
 
   target_info = RunDownloadTargetDeterminer(
       GetPathInDownloadDir(kInitialPath), item.get());
   EXPECT_FALSE(target_info->is_filetype_handled_safely);
 }
 #endif  // defined(ENABLE_PLUGINS)
 
 }  // namespace