Compile 'minijail0' on Brillo/Android.

We're not currently using the 'minijail0' executable on Brillo or
Android, but given that upstream Minijail is in AOSP, it's useful to
be able to build all Minijail targets in a Brillo or Android checkout.
Make it an "optional" target so that it doesn't get included on regular

This requires fixing one case of assigning 'const char*' to 'char*',
setting an invalid PRELOADPATH variable, and disabling
'missing-field-initializers' warnings.

Bug: 26798535
Change-Id: I1fe61f5ac2687d3a185d971a699fa4237a4b6a10
3 files changed