DO NOT MERGE Securely encrypt the master key

DO NOT MERGE Securely encrypt the master key

(cherry-picked from commit 377cd1957172c19ee21baa3d6bda0840f1ce020d)

Move all key management into vold
Reuse vold's existing key management through the crypto footer
to manage the device wide keys.

Use ro.crypto.type flag to determine crypto type, which prevents
any issues when running in block encrypted mode, as well as speeding
up boot in block or no encryption.

This is one of four changes to enable this functionality:
  https://android-review.googlesource.com/#/c/148586/
  https://android-review.googlesource.com/#/c/148604/
  https://android-review.googlesource.com/#/c/148606/
  https://android-review.googlesource.com/#/c/148607/

Bug: 18151196

Change-Id: I7a4ef3f3a937c45ff18f17c9ad1398293a8630f3