* Cleaned up MapperService#searchFilter(...) and moved it DefaultSearchContext, since it that class was the only user. As part of the cleanup percolate query documents are no longer excluded from the search response.
* Removed resolveClosestNestedObjectMapper(...) method as it was no longer used.
* Removed DocumentTypeListener infrastructure. Before it was used by the percolator and parent/child, but these features no longer use it.
Closes#15924
7914d0f940