Settings reset prompt: Fetch default settings only when needed.

chrome/browser/safe_browsing/settings_reset_prompt/default_settings_fetcher.h

Index: chrome/browser/safe_browsing/settings_reset_prompt/default_settings_fetcher.h
diff --git a/chrome/browser/safe_browsing/settings_reset_prompt/default_settings_fetcher.h b/chrome/browser/safe_browsing/settings_reset_prompt/default_settings_fetcher.h
index ffd5e9eaa8eb062a97d13c7702d80ce616948e71..8a71e4094e5525ab6c18d4d10312d212e8831bc1 100644
--- a/chrome/browser/safe_browsing/settings_reset_prompt/default_settings_fetcher.h
+++ b/chrome/browser/safe_browsing/settings_reset_prompt/default_settings_fetcher.h
@@ -25,6 +25,9 @@ class DefaultSettingsFetcher {
   // Fetches default settings and passes the corresponding
   // |BrandcodedDefaultSettings| object to |callback| on the UI thread. This
   // function must be called on the UI thread as well.
+  //
+  // If fetching of default settings on the network fails, a default-constructed
+  // BrandcodedDefaultSettings object will be passed to |callback|.
   static void FetchDefaultSettings(SettingsCallback callback);
   // Allows tests to specify the default settings that were fetched in
   // |fetched_settings|. Passing nullptr as |fetched_settings| corresponds to