Roll Observatory deps (charted -> ^0.3.0)

packages/usage/tool/travis.sh

 #!/bin/bash
 
 # Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 # Fast fail the script on failures.
 set -e
 
 # Verify that the libraries are error free.
 dartanalyzer --fatal-warnings \
   lib/usage.dart \
   lib/usage_html.dart \
   lib/usage_io.dart \
   test/all.dart
 
 # Run the tests.
-dart test/all.dart
+dart -c test/all.dart
 
 # Run the UI/web tests as well.
-pub build test
-pub run grinder:test build/test/web.html
+#pub build test
+#pub run grinder:test build/test/web.html
+
+# Verify against DDC.
+pub global activate dev_compiler
+pub global run dev_compiler lib/usage_html.dart
 
 # Measure the size of the compiled JS, for the dart:html version of the library.
 dart tool/grind.dart build
 
 # Install dart_coveralls; gather and send coverage data.
 if [ "$REPO_TOKEN" ]; then
   pub global activate dart_coveralls
   pub global run dart_coveralls report \
     --token $REPO_TOKEN \
     --retry 2 \
     --exclude-test-files \
     test/all.dart
 fi