Fixed problem with reading request values

Fixed problem with reading form and request values to internal request
collection.

src/OAuth2Provider/Extensions.cs

@@ -64,12 +64,16 @@ public static void SafeAddRange<TKey, TValue>(this IDictionary<TKey, IList<TValu
         public static void SafeAdd<TKey, T>(this IDictionary<TKey, IList<T>> dictionary, TKey key, IList<T> items)
         {
             IList<T> existingItems = null;
-            dictionary.TryGetValue(key, out items);
+            dictionary.TryGetValue(key, out existingItems);
 
             if (existingItems == null)
+            {
                 existingItems = new List<T>();
-
-            existingItems.AddRange(items);
+                existingItems.AddRange(items);
+                dictionary[key] = existingItems;
+            }
+            else
+                existingItems.AddRange(items);
         }
 
         public static string ToQueryString(this NameValueCollection nvc)
@@ -204,13 +208,13 @@ public static string ToJson(this object obj)
         public static HttpBasicAuthenticationScheme DecodeBasicAuthentication(this IRequest request)
         {
             return new HttpBasicAuthenticationScheme(request);
-        }
-
-        public static bool IsFormEncoded(this IOAuthRequest request)
-        {
-            // Content-Type may or may not include the character encoding (e.g. charset=UTF-8)
-            var contentType = request.ContentType;
-            return !string.IsNullOrEmpty(contentType) && contentType.StartsWith(ContentType.FormEncoded, StringComparison.OrdinalIgnoreCase);
+        }
+
+        public static bool IsFormEncoded(this IOAuthRequest request)
+        {
+            // Content-Type may or may not include the character encoding (e.g. charset=UTF-8)
+            var contentType = request.ContentType;
+            return !string.IsNullOrEmpty(contentType) && contentType.StartsWith(ContentType.FormEncoded, StringComparison.OrdinalIgnoreCase);
         }
     }
 }