add test for update selection by modifying bound field
ensure max line length <= 80
Cherry pick https://github.com/Polymer/core-overlay/pull/33
Merge pull request #147 from dart-lang/core-overlay

Cherry pick https://github.com/Polymer/core-overlay/pull/33
Merge branch 'master' of github.com:dart-lang/core-elements into core-list-dart-test
#144
Fixes according to review comments
Merge pull request #140 from zoechi/core-list-dart-test

add test for update selection by modifying bound field
Cherry-pick fix to core-focusable.js
Merge pull request #151 from dart-lang/fix_core_focusable

Cherry-pick fix to core-focusable.js
fix the core-style example in pub serve
Merge pull request #153 from dart-lang/fix-example

fix the core-style example in pub serve
add runtime warnings about core-list-dart content'
added notes about what the core-list-dart content should look like
add TODO