Fix changelog for release (dart-lang/string_scanner#13)

Fixes https://github.com/dart-lang/string_scanner/issues/12

pkgs/string_scanner/CHANGELOG.md

diff --git a/pkgs/string_scanner/CHANGELOG.md b/pkgs/string_scanner/CHANGELOG.md
index 3602fb3..43b9453 100644
--- a/pkgs/string_scanner/CHANGELOG.md
+++ b/pkgs/string_scanner/CHANGELOG.md
@@ -1,4 +1,4 @@
-## 1.1.0
+## 1.0.4
 
 * Add @alwaysThrows annotation to error method.