Bug 1688833 - Migrate LookupForAdd to WithEntryHandle in dom/localstorage. r=dom-storage-reviewers,janv

Differential Revision: https://phabricator.services.mozilla.com/D104194

dom/localstorage/ActorsParent.cpp

@@ -5435,8 +5435,8 @@ void Snapshot::SaveItem(const nsAString& aKey, const LSValue& aOldValue,
   }
 
   if (!mLoadedItems.GetEntry(aKey) && !mUnknownItems.GetEntry(aKey)) {
-    LSValue oldValue(aOldValue);
+    mValues.WithEntryHandle(aKey,
-    mValues.LookupForAdd(aKey).OrInsert([oldValue]() { return oldValue; });
+                            [&](auto&& entry) { entry.OrInsert(aOldValue); });
   }
 
   if (aAffectsOrder && !mSavedKeys) {

dom/localstorage/LSSnapshot.cpp

@@ -731,14 +731,14 @@ nsresult LSSnapshot::GetItemInternal(const nsAString& aKey,
       if (aValue.WasPassed()) {
         const nsString& value = aValue.Value();
         if (!value.IsVoid()) {
-          auto entry = mValues.LookupForAdd(aKey);
+          mValues.WithEntryHandle(aKey, [&](auto&& entry) {
-          if (entry) {
+            if (entry) {
-            result = entry.Data();
+              result = std::exchange(entry.Data(), value);
-            entry.Data() = value;
+            } else {
-          } else {
+              result.SetIsVoid(true);
-            result.SetIsVoid(true);
+              entry.Insert(value);
-            entry.OrInsert([value]() { return value; });
+            }
-          }
+          });
         } else {
           if (auto entry = mValues.Lookup(aKey)) {
             result = entry.Data();