enable developer options visibility by default for userdebug builds (credit romanbb)

Change-Id: I14bcb6953ce6a6aa268f1194b0bb3ebb9d0b5df4
One does not simply become a Developer (credit chirayudesai)

Change-Id: I6ba232418bb5f6ffcd4c94f54b48b9c6142b71ad
Merge changes I6ba23241,I14bcb695 into jellybean

* changes:
  One does not simply become a Developer (credit chirayudesai)
  enable developer options visibility by default for userdebug builds (credit romanbb)