Merge "Refactor keystore."
am: e4f2fa54b0

* commit 'e4f2fa54b009838f72219735d692d84d062a0177':
  Refactor keystore.
tree: b746ed05a0889ec3bc947336829e2ca9c0076eb2
  1. keystore/
  2. keystore-engine/
  3. softkeymaster/
  4. MODULE_LICENSE_APACHE2
  5. NOTICE