Encrypt /data/misc

Now we have a workaround for 26989796 (we don't touch /data/misc/vold
thanks to:
    https://googleplex-android-review.git.corp.google.com/#/c/862867
) we can check this in and remove the need for a data wipe when we land
the proper kernel fix for this issue (stop caching negative file lookups
through a key change)

Bug: 26989796
Change-Id: I83e6b8395b2c6a607b692dc9cf71183b13680071
1 file changed