Scripts that need to be recompiled are not displayed in the UI

To reproduce this; change a built-in script that you have under the script roots and refresh the built-in scripts page to force a recompile.

That script is no longer visible under the built-in scripts menu. You will see something like the following in the logs.

2017-08-11 11:24:38 [http-nio-8080-exec-8] WARN  c.o.s.r.rest.AbstractRestEndpoint - Failed to instantiate com.onresolve.scriptrunner.canned.bitbucket.admin.ListRepositorySizes, null

This is caused by when we get the bundle for the script there is no bundle after recompilation so it assumes it's a script plugin.

This is not just for built-in scripts but for almost all script items.