Check if BACKDROP_ROOT is defined already

[laryn]

Overview

I'm seeing this in my Backdrop watchdog log:

Notice: Constant BACKDROP_ROOT already defined in CRM_Utils_System_Backdrop->loadBootStrap() (line 526 of /app/modules/civicrm/CRM/Utils/System/Backdrop.php).

We should check to see if the constant is already defined before defining it again.

[civibot]

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[eileenmcnaughton]

@laryn this makes sense - jenkin wants you to use 2 space indent though - see the failing check

@herbdool

[laryn]

Thanks @eileenmcnaughton this is what comes of editing in the Github UI to submit a PR 😬

[herbdool]

Looks good to me.

[eileenmcnaughton]

unrelated test fail