Ensure tests have an active task runner

chrome/browser/ui/passwords/password_bubble_experiment_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 "chrome/browser/ui/passwords/password_bubble_experiment.h"
 
 #include "base/files/scoped_temp_dir.h"
 #include "base/metrics/field_trial.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/string_number_conversions.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_profile.h"
 #include "components/variations/entropy_provider.h"
 #include "components/variations/variations_associated_data.h"
+#include "content/public/test/test_browser_thread_bundle.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 const char kGroupName[] = "SomeGroupName";
 const int kNopeThreshold = 10;
 
 void SetupExperiment() {
   ASSERT_TRUE(base::FieldTrialList::CreateFieldTrial(
       password_bubble_experiment::kExperimentName,
@@ skipping 19 matching lines @@
         new metrics::SHA1EntropyProvider("foo")));
   }
 
   void TearDown() override {
     variations::testing::ClearAllVariationParams();
   }
 
   PrefService* prefs() { return profile_->GetPrefs(); }
 
  private:
+  content::TestBrowserThreadBundle thread_bundle_;
   base::ScopedTempDir temp_dir_;
   scoped_ptr<TestingProfile> profile_;
   scoped_ptr<base::FieldTrialList> field_trial_list_;
 };
 
 TEST_F(PasswordBubbleExperimentTest, NoExperiment) {
   EXPECT_FALSE(
       password_bubble_experiment::ShouldShowNeverForThisSiteDefault(prefs()));
   for (int i = 0; i <= kNopeThreshold; ++i) {
     password_bubble_experiment::RecordBubbleClosed(
@@ skipping 43 matching lines @@
       password_bubble_experiment::ShouldShowNeverForThisSiteDefault(prefs()));
   // Repeatedly click "Never". It shouldn't affect the state.
   for (int i = 0; i < kNopeThreshold; ++i) {
     password_manager::metrics_util::UIDismissalReason reason =
         password_manager::metrics_util::CLICKED_NEVER;
     password_bubble_experiment::RecordBubbleClosed(prefs(), reason);
   }
   EXPECT_TRUE(
       password_bubble_experiment::ShouldShowNeverForThisSiteDefault(prefs()));
 }