Merge cherrypicks of [8558068, 8558825, 8558826, 8558827, 8557109, 8558018, 8558886, 8558887, 8558888, 8558889, 8558071, 8558072, 8556231] into qt-release

Change-Id: I85b0f712fdac7216a9deb1c6ade7be0b668d6e86
tree: 84cbf81a54186ff30f07123f7b239d15309759fa
  1. prebuilt/
  2. Android.mk
  3. CleanSpec.mk
  4. README