Merge "ApkSignerEngine abstraction for apksigner-core library."
am: afd3d55261

* commit 'afd3d55261df842767eca58afc55a241e71c0975':
  ApkSignerEngine abstraction for apksigner-core library.

Change-Id: Iac53d76ce67882ae73842d9ecb182ea21fb81f70