dirstate: stop gathering parentfiledata in update_file
Gathering information here assume that they are valid cache information for a
clean file. It is true most of the time, but not garanteed.
Accurate data can still be explicitly provided.
We drop the spontaneous and will let the next `hg status` call record actual information.
Differential Revision: https://phab.mercurial-scm.org/D11791
(binary:application/octet-stream)