Revert "Remove the emulator special case from the "adb root" code."

adb root doesn't work on the emulator, so this prevents root access
to a userdebug emulator.

Since the emulator has always been root even on userdebug builds, it
may be that adb root has never worked on the emulator.

Bug: 19974213

This reverts commit abd6773b41effd1e1005ad7ce8cb5e370a367302.
1 file changed