installd: Create VDEX files and pass their FDs to dex2oat

ART now produces a new output file called VDEX, produced alongside the
existing OAT file. This patch updates installd to compute the VDEX's
path, open it and pass the file descriptor to dex2oat.

Bug: 30937355
Change-Id: Ib5c327f1f7a36cfa0b89084d5c01b6da9f8108f2
1 file changed