Mechanical refactoring to new XML resolvers.

Related changes are introducing new TypedXmlSerializer and
TypedXmlPullParser interfaces which offer efficient access to
primitive attributes.

This change is a purely mechanical refactoring to prepare for
upcoming data format shifts, and has no behavior changes.

Bug: 171832118
Test: manual
Change-Id: Iad9796ce32bc449491c34c31f1f9a4b44efbcda4