Bug 1895978 - Add the new clear on shutdown cache pref to the cache purging task code. r=pbz,necko-reviewers,valentin

Differential Revision: https://phabricator.services.mozilla.com/D210681

modules/libpref/init/StaticPrefList.yaml

@@ -14217,6 +14217,11 @@
   value: 1000
   mirror: always
 
+- name: privacy.sanitize.useOldClearHistoryDialog
+  type: RelaxedAtomicBool
+  value: true
+  mirror: always
+
 - name: privacy.sanitize.sanitizeOnShutdown
   type: RelaxedAtomicBool
   value: false
@@ -14227,6 +14232,11 @@
   value: false
   mirror: always
 
+- name: privacy.clearOnShutdown_v2.cache
+  type: RelaxedAtomicBool
+  value: false
+  mirror: always
+
 - name: privacy.dynamic_firstparty.limitForeign
   type: RelaxedAtomicBool
   value: false

netwerk/cache2/CacheObserver.h

@@ -73,8 +73,14 @@ class CacheObserver : public nsIObserver, public nsSupportsWeakReference {
   }
   static uint32_t HalfLifeSeconds() { return sHalfLifeHours * 60.0F * 60.0F; }
   static bool ClearCacheOnShutdown() {
-    return StaticPrefs::privacy_sanitize_sanitizeOnShutdown() &&
+    if (!StaticPrefs::privacy_sanitize_sanitizeOnShutdown()) {
-           StaticPrefs::privacy_clearOnShutdown_cache();
+      return false;
+    }
+    if (StaticPrefs::privacy_sanitize_useOldClearHistoryDialog()) {
+      return StaticPrefs::privacy_clearOnShutdown_cache();
+    }
+    // use the new cache clearing pref for the new clear history dialog
+    return StaticPrefs::privacy_clearOnShutdown_v2_cache();
   }
   static void ParentDirOverride(nsIFile** aDir);