Version 1.21.0

Merge 15400c01f06ddb8536afea6b5dad5099973e1aa3 into stable
diff --git a/CHANGELOG.md b/CHANGELOG.md
index b90703a..141f621 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,4 @@
-## 1.21.0
+## 1.21.0 - 2016-12-07
 
 ### Language
 
diff --git a/tools/VERSION b/tools/VERSION
index 392d057..fef80b6 100644
--- a/tools/VERSION
+++ b/tools/VERSION
@@ -24,9 +24,9 @@
 #  * Making cherry-picks to stable channel
 #     - increase PATCH by 1
 #
-CHANNEL dev
+CHANNEL stable
 MAJOR 1
 MINOR 21
 PATCH 0
-PRERELEASE 11
-PRERELEASE_PATCH 3
+PRERELEASE 0
+PRERELEASE_PATCH 0