Use for-loop to iterate over codeUnits in number formatter.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118970435
diff --git a/lib/src/intl/number_format.dart b/lib/src/intl/number_format.dart
index b31fa91..069936b 100644
--- a/lib/src/intl/number_format.dart
+++ b/lib/src/intl/number_format.dart
@@ -494,8 +494,8 @@
     for (var i = 0; i < numberOfDigits - basic.length; i++) {
       _add(symbols.ZERO_DIGIT);
     }
-    for (var x in basic.codeUnits) {
-      _addDigit(x);
+    for (int i = 0; i < basic.codeUnits.length; i++) {
+      _addDigit(basic.codeUnits[i]);
     }
   }