Merge changes from topic 'secondary-dex'

* changes:
  Fix typo in dexopt.secondary system property
  Save package dex usage info after secondary dex reconciliation
  Compile secondary dex files during background dexopt job
  Add a shell command to force the background dexopt job
  A bit more refactoring in BackgroundDexOptService
  [PM] Clean up logic for secondary dex oat files
  Compile secondary dex files in DexManager
  Notify DexManager about new package installs