Prepare to publish stable null safety (#23)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index afa0580..b887dee 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 1.2.0
+
+* Stable release for null safety.
+
 ## 1.2.0-nullsafety.3
 
 * Update SDK constraints to `>=2.12.0-0 <3.0.0` based on beta release
diff --git a/pubspec.yaml b/pubspec.yaml
index faf7f14..96063f6 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: charcode
-version: 1.2.0-nullsafety.3
+version: 1.2.0
 repository: https://github.com/lrhn/charcode
 description: >-
   Constants for ASCII and common non-ASCII character codes.