Add pointer size logic to InitFromImageInterpretOnly

Previously we didn't have this logic which broke dex2oat if passed
--runtime-option -Xint flag.

Also we now no longer call InitFromImageInterpretOnlyCallback if
we are the compiler.

Bug: 18631640
Change-Id: Ie84fceeb85cabeeec7a5fedefd73dd919cca8e5e
2 files changed