Settings reset prompt: Enable the feature for fieldtrial testing.

chrome/browser/safe_browsing/settings_reset_prompt/settings_reset_prompt_config.h

 // 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.
 
 #ifndef CHROME_BROWSER_SAFE_BROWSING_SETTINGS_RESET_PROMPT_SETTINGS_RESET_PROMPT_CONFIG_H_
 #define CHROME_BROWSER_SAFE_BROWSING_SETTINGS_RESET_PROMPT_SETTINGS_RESET_PROMPT_CONFIG_H_
 
 #include <cstddef>
 #include <memory>
 #include <string>
@@ skipping 47 matching lines @@
   };
   enum ConfigError : int;
 
   bool Init();
   ConfigError ParseDomainHashes(const std::string& domain_hashes_json);
 
   // Map of 32 byte SHA256 hashes to integer domain IDs.
   std::unordered_map<SHA256Hash, int, SHA256HashHasher> domain_hashes_;
 
   // Other feature parameters.
+  //
+  // If you add any required feature parameters, make sure to update the field
+  // trial testing configuration for the "SettingsResetPrompt" feature in
+  // src/testing/variations/fieldtrial_testing_config.json
   base::TimeDelta delay_before_prompt_;
   int prompt_wave_ = 0;
   base::TimeDelta time_between_prompts_;
 
   DISALLOW_COPY_AND_ASSIGN(SettingsResetPromptConfig);
 };
 
 }  // namespace safe_browsing
 
 #endif  // CHROME_BROWSER_SAFE_BROWSING_SETTINGS_RESET_PROMPT_SETTINGS_RESET_PROMPT_CONFIG_H_