Minor fixes to KeepScanner tool:
- use Guava to read zip entries
- Fix keep rules emitted for constructors
RELNOTES: None.

PiperOrigin-RevId: 188781547
GitOrigin-RevId: 8e038b04e068285ba02b7934a7df25803802daff
Change-Id: Ifc99978b041f9c1c97ff707aafac90c59187c6c8
2 files changed
tree: dd807dc6e0b72a0f86c7a98ad225ea02bd79db27
  1. java/
  2. test/