Archive or update unsupported Android scripts and third-party dependencies.

  - nothing uses ashmem;
  - cpufeatures and native_app_glue are now pulled from the NDK;
  - no bots use the scripts in platform_tools/android/bin;
  - update scripts to work with GN instead of GYP.

Change-Id: I14f47eeadb3047505e232dd10385f58ef12c73f4
Reviewed-on: https://skia-review.googlesource.com/5422
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Derek Sollenberger <djsollen@google.com>
27 files changed