Update the encryption password when the device password is changed.

* Added changeEncryptionPassword() to the MountService.
* Update LockPatternUtils to call changeEncryptionPassword()
  when the password is changed.

Note we only require the new password to change the
encryption password.

Bug: 3382129
Change-Id: I26a7e919e325e75e22fa4290da0a8b1b57b55a80
3 files changed