Bug 1346313 - Part 1: Modify Fetch's header handler delimiter to 0x2C 0x20 to align with spec. r=baku

dom/fetch/InternalHeaders.cpp

@@ -88,7 +88,7 @@ InternalHeaders::Get(const nsACString& aName, nsACString& aValue, ErrorResult& a
     return;
   }
 
-  const char* delimiter = ",";
+  const char* delimiter = ", ";
   bool firstValueFound = false;
 
   for (uint32_t i = 0; i < mList.Length(); ++i) {