Raw attribute values are not included in xml files when building binary APKs but they are when building proto APKs. Remove raw attribute values and create a new convert flag that (--keep-raw-values) that allows raw value to be kept. Also added flag to link to keep raw attribute values. Bug: 115915884 Bug: 116700688 Test: aapt2_tests Change-Id: Id50136b775b3f43d159ca06181282f6a7b8eaf40