Hack to modify xxxSdVersion for building pre-N apk against preview SDK
Hack to modify xxxSdVersion for building pre-N apk against preview SDK

Modify the minSdkVersion and targetSdkVersion in generated manifest

Change-Id: I8470693c0a316a3ad12a196bdd8f1c257da9e6c8

googlesamples/android-testdpc,googlesamples/android-testdpc