Bug 1682536 - Use references/NotNull for QuotaObject. r=dom-workers-and-storage-reviewers,janv

Differential Revision: https://phabricator.services.mozilla.com/D99780

dom/quota/ActorsParent.cpp

@@ -841,7 +841,7 @@ class OriginInfo final {
 
   void LockedPersist();
 
-  nsDataHashtable<nsStringHashKey, QuotaObject*> mQuotaObjects;
+  nsDataHashtable<nsStringHashKey, NotNull<QuotaObject*>> mQuotaObjects;
   ClientUsageArray mClientUsages;
   GroupInfo* mGroupInfo;
   const nsCString mOrigin;
@@ -4341,15 +4341,16 @@ already_AddRefed<QuotaObject> QuotaManager::GetQuotaObject(
     // We need this extra raw pointer because we can't assign to the smart
     // pointer directly since QuotaObject::AddRef would try to acquire the same
     // mutex.
-    QuotaObject* quotaObject;
-    if (!originInfo->mQuotaObjects.Get(path, &quotaObject)) {
-      // Create a new QuotaObject.
-      quotaObject = new QuotaObject(originInfo, aClientType, path, fileSize);
-
-      // Put it to the hashtable. The hashtable is not responsible to delete
-      // the QuotaObject.
-      originInfo->mQuotaObjects.Put(path, quotaObject);
-    }
+    const NotNull<QuotaObject*> quotaObject =
+        originInfo->mQuotaObjects.WithEntryHandle(
+            path, [&](auto&& entryHandle) {
+              return entryHandle.OrInsertWith([&] {
+                // Create a new QuotaObject. The hashtable is not responsible to
+                // delete the QuotaObject.
+                return WrapNotNullUnchecked(
+                    new QuotaObject(originInfo, aClientType, path, fileSize));
+              });
+            });
 
     // Addref the QuotaObject and move the ownership to the result. This must
     // happen before we unlock!