Ignore resources from unknown types

When loading binary APKs into aapt2 for dumping purposes, aapt2 allows
the presence of custom resource types in the resources.arsc. Since
apapt2 may not be able to correctly interpret the data of custom types,
ignore resources from custom types completely when constructing the
ResourceTable data structure for the APK.

Bug: 168247188
Bug: 36051266
Test: run aapt2 dump bading/resources on APKs from both bugs
Merged-In: Ia3c0b4e07457eb8634b5a256ef77270e99b8bd72
Change-Id: Ia3c0b4e07457eb8634b5a256ef77270e99b8bd72