[Progress on 67046576]: add sharing to Bounce
Merge branch 'master' of https://github.com/code-dot-org/blockly into pivotal_67046576
[Finishes 67046576]: Enable bounce sharing
cosmetic flappy changes: adjust share button height, don't draw square or border around 400x400 image
Merge pull request #460 from code-dot-org/pivotal_67046576

Pivotal 67046576: enable sharing of bounce - on new last level