Merge changes I89826fc2,Ica0c14da,Icfbb799f,I233bbc7b,I30569a7c, ...

* changes:
  adb-remount-test: check devt and inode
  adb-remount-test: add an avc check
  adb-remount-test: parameterize fastboot_wait & adb_wait, increase timeout
  adb-remount-test: report wait duration
  adb-remount-test: check vendor image signature before using
  adb-remount-test: report usb user on unexpected connection
  adb-remount-test: wait-for-screen