AI 144950: Manual integration of 144342 and 144547 from donutburger to cupcake.
Fix bag (string-array, etc) behavior with overlays.
We used to replace elements in the default with elements from the
overlay. This change causes us to empty the array first so if the
overlay array is smaller we don't end up with elements from the
default array showing through at the end of the final result.
Ex: [A,B,C] default with [D] overlay should give [D] but used to
give [D,B,C]
BUG=
1754390
Automated import of CL 144950
AI 144308: aapt extensions: required sdk version, dependent software libraries, gadgets
Add new attributes for sdk version, software libs and gadgets
BUG =
1730924
BUG=
1730924
Automated import of CL 144308