Cipher: always select a SPI in init according to the parameters

Behaviour before this CL was to avoid selecting a SPI if there
was a previously selected one. That is an incompatibility wrt M.

This CL makes Cipher compatible with the M behaviour

(cherry picked from commit 264d21f1e86e7ec7976fc5346c21a8e17d8635b1)

Bug: 29038928
Change-Id: Iad68ec2c1eca99c4e98f5179429498cff9b42c36
3 files changed