ART: Fix swap usage determination in dex2oat

The decision needs to be postponed until we have access to the
dex files.

Bug: 27878043

(cherry picked from commit ce55f0d4da1db20676273032b3c79624f665b35b)

Change-Id: I55833c6ea827ec7a322711bd182fc723d1727f08
1 file changed