am 282cb814: am 10a1d761: am 20228de2: Flesh out dex-preopt a bit more.

Merge commit '282cb814c1324273098adb496cc15d4f007b54d2' into dalvik-dev

* commit '282cb814c1324273098adb496cc15d4f007b54d2':
  Flesh out dex-preopt a bit more.