am e5a8cd42: am 96604831: First possibly-working cut of dex-preopt.

Merge commit 'e5a8cd42a5d9ab9c8466fe7b333f94fe1a034f52'

* commit 'e5a8cd42a5d9ab9c8466fe7b333f94fe1a034f52':
  First possibly-working cut of dex-preopt.