Fix TestBrowserThread destruction order in CrOS tests.

chrome/browser/chromeos/hats/hats_finch_helper_unittest.cc

 // Copyright 2016 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/chromeos/hats/hats_finch_helper.h"
 
 #include <map>
 
 #include "base/strings/string_number_conversions.h"
 #include "base/test/scoped_feature_list.h"
@@ skipping 39 matching lines @@
                           std::string reset) {
     ParamMap params;
     params[HatsFinchHelper::kProbabilityParam] = prob;
     params[HatsFinchHelper::kSurveyCycleLengthParam] = cycle_length;
     params[HatsFinchHelper::kSurveyStartDateMsParam] = start_date;
     params[HatsFinchHelper::kResetSurveyCycleParam] = reset_survey;
     params[HatsFinchHelper::kResetAllParam] = reset;
     return params;
   }
 
+ private:
+  // Must outlive |profile_|.
+  content::TestBrowserThreadBundle thread_bundle_;
+
+ protected:
   TestingProfile profile_;
 
  private:
   variations::testing::VariationParamsManager params_manager_;
-  content::TestBrowserThreadBundle thread_bundle_;
   base::test::ScopedFeatureList scoped_feature_list_;
 
   DISALLOW_COPY_AND_ASSIGN(HatsFinchHelperTest);
 };
 
 TEST_F(HatsFinchHelperTest, InitFinchSeed_ValidValues) {
   ParamMap params =
       CreateParamMap("1.0", "7", "1475613895337", "false", "false");
   SetFinchSeedParams(params);
 
@@ skipping 93 matching lines @@
             2 * current_time.ToJsTime());
 
   EXPECT_FALSE(pref_service->GetBoolean(prefs::kHatsDeviceIsSelected));
   EXPECT_NE(pref_service->GetInt64(prefs::kHatsSurveyCycleEndTimestamp),
             initial_timestamp);
   EXPECT_NE(pref_service->GetInt64(prefs::kHatsLastInteractionTimestamp),
             initial_timestamp);
 }
 
 }  // namespace chromeos