[ImportantSites] Implementing dialog level blacklisting and blacklist expiration

chrome/browser/engagement/important_sites_util.h

Index: chrome/browser/engagement/important_sites_util.h
diff --git a/chrome/browser/engagement/important_sites_util.h b/chrome/browser/engagement/important_sites_util.h
index c6259358d959f24f5ae8e69d775fb82413021643..408dff05d7c3f92d8115c2b426b2f2caca2629b0 100644
--- a/chrome/browser/engagement/important_sites_util.h
+++ b/chrome/browser/engagement/important_sites_util.h
@@ -13,6 +13,10 @@
 
 class Profile;
 
+namespace user_prefs {
+class PrefRegistrySyncable;
+}
+
 class ImportantSitesUtil {
  public:
   struct ImportantDomainInfo {
@@ -22,6 +26,10 @@ class ImportantSitesUtil {
     int32_t reason_bitfield = 0;
   };
 
+  static bool IsDialogDisabled(Profile* profile);
+
+  static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
+
   // This returns the top |<=max_results| important registrable domains. This
   // uses site engagement and notifications to generate the list. |max_results|
   // is assumed to be small.