Branches scuba2.proto to Android git master.

We need to branch scuba2.proto to Android to build a solution to
Android's screenshot diff tests.
The original scuba2.proto is located below:
//testing/screendiffing/proto/scuba2.proto

Bug: 218909505
Bug: 223900672
Test: No test needed to only branch proto definitions.
Change-Id: I8680217cc62bd198e610e1c5e39b7835a48392f3
2 files changed
tree: a1f3ebb50354aabb676782052a9c8a2749853c2a
  1. build/
  2. docs/
  3. emu_test/
  4. libraries/
  5. scripts/
  6. tests/
  7. utils/
  8. PREUPLOAD.cfg