Switch Travis to the stable Dart SDK

abarth · abarth · commit 8a06b8360727 · 2015-11-21T11:59:29.000-08:00
Hopefully this will make Travis green.
diff --git a/.travis.yml b/.travis.yml
@@ -1,7 +1,7 @@
 language: dart
 sudo: false
 dart:
-  - dev
+  - stable
 addons:
   apt:
     sources:
