Improve the androidmk makefile parser based on ideas from go/ast and
friends:
- Use type switching instead of the As* mess
- Don't store endPos for every node, compute it based on the last
known position in the node plus the length of the last token
- Store positions as only the offset into the file, and then unpack
them into Line/Column scanner.Position objects later
Change-Id: I87eb6661859951e6c2ea5a85db6229fa5561d615
Initial build logic for building android with soong. It can build
a variety of C and C++ files for arm/arm64 and host.
Change-Id: I10eb37c2c2a50be6af1bb5fd568c0962b9476bf0
