Tighten up a couple method signatures to specify that int is required.

lib/src/intl/date_format_helpers.dart

Index: lib/src/intl/date_format_helpers.dart
diff --git a/lib/src/intl/date_format_helpers.dart b/lib/src/intl/date_format_helpers.dart
index 1b42d89c48db2c1b58e29aa7ae6dcf532a3e9e7a..13b38017c36aaa8ad07dbdb47b3bbf76cba3bc47 100644
--- a/lib/src/intl/date_format_helpers.dart
+++ b/lib/src/intl/date_format_helpers.dart
@@ -124,7 +124,7 @@ class _Stream {
    * Return the next [howMany] items, or as many as there are remaining.
    * Advance the stream by that many positions.
    */
-  read([howMany = 1]) {
+  read([int howMany = 1]) {
     var result = peek(howMany);
     index += howMany;
     return result;
@@ -143,7 +143,7 @@ class _Stream {
    * Return the next [howMany] items, or as many as there are remaining.
    * Does not modify the stream position.
    */
-  peek([howMany = 1]) {
+  peek([int howMany = 1]) {
     var result;
     if (contents is String) {
       result = contents.substring(