Programatically make Reset button at least as wide as Run button.
In a future CL, I will remove the padding from the resetButton message.
This will simplify translation.

R=neil.fraser@gmail.com

Review URL: https://codereview.appspot.com/8812057

git-svn-id: http://blockly.googlecode.com/svn/trunk@786 c400ca83-b69d-9dd7-9705-49c6b8615e23