mozilla-b2g/gaia — pull request #4257 by jhford (2012-08-31 22:18:07+00:00)
Title: automatically clean xulrunner when we change the xulrunner url

Whenever xulrunner changes, we should automatically clean out the current xulrunner if it isn't the correct one.

This change has the same shell overhead as the current version of the target, one shell call if nothing needs to be done. Previously, that was done as part of the target's body, but now it's done to figure out whether to include the logic to purge, grab and set up xulrunner.