Do not tie cleanup tool download to SRTPromptFieldTrial field trial

chrome/browser/safe_browsing/chrome_cleaner/srt_field_trial_win_unittest.cc

 // Copyright 2017 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/safe_browsing/chrome_cleaner/srt_field_trial_win.h"
 
 #include <map>
 #include <string>
 
-#include "base/metrics/field_trial.h"
 #include "base/win/windows_version.h"
-#include "components/variations/variations_associated_data.h"
+#include "components/variations/variations_params_manager.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace safe_browsing {
 
 class SRTDownloadURLTest : public ::testing::Test {
  protected:
-  void SetUp() override {
-    field_trial_list_ = std::make_unique<base::FieldTrialList>(nullptr);
-  }
-
-  void CreatePromptTrial(const std::string& experiment_name,
-                         const std::string& download_group) {
-    std::map<std::string, std::string> params;
-    if (!download_group.empty())
-      params["download_group"] = download_group;
-
-    // Assigned trials will go out of scope when field_trial_list_ goes out
-    // of scope.
+  void CreatePromptTrial(const std::string& experiment_name) {
+    // Assigned trials will go out of scope when variations_ goes out of scope.
     constexpr char kTrialName[] = "SRTPromptFieldTrial";
-    variations::AssociateVariationParams(kTrialName, experiment_name, params);
     base::FieldTrialList::CreateFieldTrial(kTrialName, experiment_name);
   }
 
+  void CreateDownloadFeature(const std::string& download_group_name) {
+    constexpr char kFeatureName[] = "DownloadCleanupToolByBitness";
+    std::map<std::string, std::string> params;
+    params["download_group"] = download_group_name;
+    variations_.SetVariationParamsWithFeatureAssociations(
+        "A trial name", params, {kFeatureName});
+  }
+
  private:
-  std::unique_ptr<base::FieldTrialList> field_trial_list_;
+  variations::testing::VariationParamsManager variations_;
 };
 
 TEST_F(SRTDownloadURLTest, Stable) {
-  CreatePromptTrial("On", "");
+  CreatePromptTrial("On");
   EXPECT_EQ("/dl/softwareremovaltool/win/chrome_cleanup_tool.exe",
             GetSRTDownloadURL().path());
 }
 
 TEST_F(SRTDownloadURLTest, Canary) {
-  CreatePromptTrial("SRTCanary", "");
+  CreatePromptTrial("SRTCanary");
   EXPECT_EQ("/dl/softwareremovaltool/win/c/chrome_cleanup_tool.exe",
             GetSRTDownloadURL().path());
 }
 
 TEST_F(SRTDownloadURLTest, Experiment) {
-  CreatePromptTrial("Experiment", "experiment");
+  CreateDownloadFeature("experiment");
   std::string expected_path;
   if (base::win::OSInfo::GetInstance()->architecture() ==
       base::win::OSInfo::X86_ARCHITECTURE) {
     expected_path =
         "/dl/softwareremovaltool/win/x86/experiment/chrome_cleanup_tool.exe";
   } else {
     expected_path =
         "/dl/softwareremovaltool/win/x64/experiment/chrome_cleanup_tool.exe";
   }
   EXPECT_EQ(expected_path, GetSRTDownloadURL().path());
 }
 
 TEST_F(SRTDownloadURLTest, DefaultsToStable) {
   EXPECT_EQ("/dl/softwareremovaltool/win/chrome_cleanup_tool.exe",
             GetSRTDownloadURL().path());
 }
 
 }  // namespace safe_browsing