Comment that testNoDebuggingFeaturesRestriction fails if adb is running as root.

If adb is running as root, then the adb uid is 0 instead of SHELL_UID
so the DISALLOW_DEBUGGING_FEATURES restriction does not work and
testNoDebuggingFeaturesRestriction fails.

BUG:18927963

Change-Id: Ifbff9900a7db59dd996e22af69724cfc43e949ff
1 file changed