Specify --webroot to the Windows service wrapper

[jglick]

Otherwise we default to the war subdirectory of Jenkins home, which is

• inefficient, if this is on a slower shared drive
• dangerous, if using CloudBees high availability

Compare for example the RPM package which already sets --webroot.

@reviewbybees

[ghost]

This pull request originates from a CloudBees employee. At CloudBees, we require that all pull requests be reviewed by other CloudBees employees before we seek to have the change accepted. If you want to learn more about our process please see this explanation.

[recena]

🐝

[jglick]

Test failure looks unrelated.

@svanoort you probably want to review this.

[svanoort]

@jglick 🐝 although does need testing.

[jglick]

@svanoort yes…and do you volunteer to do that testing? (Do you have relevant infrastructure set up?)

[svanoort]

@jglick Oh, I assumed the change had been tested already (was just checking that). I think @jtnord may have something rigged up for windows testing though (I know he's got a flow up for the windows build anyway). (As always for these, infra is a huge part of the challenge.)

[jglick]

The user experiencing the problem made the corresponding edit to the jenkins.xmls in their existing service wrappers and confirmed that this fixed the problem. However the source change has not been tested in the sense of creating a fresh Windows service from a Jenkins WAR built using this patch.

[oleg-nenashev]

Seems that testing of this fix is my business :(
🐝 from what I see, but I'll verify it manually.

[oleg-nenashev]

Test failure is unrelated

[jtnord]

🐝

[oleg-nenashev]

Don't forget changelogs!