This is a follow-up commit similar to 68de1440, with more places in the
backend code simplified with the macros able to assign values to the
fields of ObjectAddress.  The code paths changed here could be
transitioned later into using more grouping when inserting dependency
records, simplifying this future work.

Author: Daniel Gustafsson, Michael Paquier
Discussion: https://postgr.es/m/20190213182737.mxn6hkdxwrzgxk35@alap3.anarazel.de