Minor refactor.

src/Volo.Abp/Volo/Abp/Localization/AbpStringLocalizerFactory.cs

@@ -48,9 +48,10 @@ namespace Volo.Abp.Localization
             
             //Notes: Localizer will be cached, so wrappers are responsible to cache/invalidate themselves!
 
-            var baseLocalizers = resource.BaseResourceTypes.Select(Create).ToList();
-
-            var localizer = new AbpDictionaryBasedStringLocalizer(resource, baseLocalizers);
+            var localizer = new AbpDictionaryBasedStringLocalizer(
+                resource,
+                resource.BaseResourceTypes.Select(Create).ToList()
+            );
 
             //TODO: Wrap with DB provider or other premium sources
 

src/Volo.Abp/Volo/Abp/Localization/ILocalizationDictionary.cs

@@ -27,5 +27,7 @@ namespace Volo.Abp.Localization
         /// </summary>
         /// <returns>List of all <see cref="LocalString"/> object</returns>
         IReadOnlyList<LocalString> GetAllStrings();
+
+        void Extend(ILocalizationDictionary dictionary);
     }
 }

src/Volo.Abp/Volo/Abp/Localization/LocalizationDictionary.cs

@@ -43,6 +43,14 @@ namespace Volo.Abp.Localization
             return _dictionary.Values.ToImmutableList();
         }
 
+        public void Extend(ILocalizationDictionary dictionary)
+        {
+            foreach (var localizedString in dictionary.GetAllStrings())
+            {
+                this[localizedString.Name] = localizedString;
+            }
+        }
+
         /// <inheritdoc/>
         public virtual IEnumerator<LocalString> GetEnumerator()
         {

src/Volo.Abp/Volo/Abp/Localization/LocalizationDictionaryProviderBase.cs

@@ -34,15 +34,7 @@ namespace Volo.Abp.Localization
             }
             else
             {
-                Overwrite(existingDictionary, dictionary);
-            }
-        }
-
-        protected virtual void Overwrite(ILocalizationDictionary existingDictionary, ILocalizationDictionary dictionary)
-        {
-            foreach (var localizedString in dictionary.GetAllStrings())
-            {
-                existingDictionary[localizedString.Name] = localizedString;
+                existingDictionary.Extend(dictionary);
             }
         }
     }