Merge change 20313 into donut

* changes:
  add feature to strip "# comment" lines from prebuilt files
tree: 2f344ac41b9ea1a0297a17c48fcff8f693f7fbc6
  1. core/
  2. libs/
  3. target/
  4. tools/
  5. buildspec.mk.default
  6. cleanspec.mk
  7. envsetup.sh