amend: stop specifying matcher, get all copies in wctx When we're recreating the commit that we'll be committing, we don't want to filter our copy information based on just the *new* [versions of the] files we're amending. The test has an example of this case, but for clarity, the situation is: ``` $ hg cp src dst && hg commit <do some work> $ hg amend some_unrelated_file.txt $ hg status --copies A dst A some_unrelated_file.txt ``` What *should* happen is that `dst` should remain marked as a copy of `src`, but this did not previously happen. `matcher` here only includes the files that were specified on the commandline, so it only gets the copy information (if any, in this example there's not) for `some_unrelated_file.txt`. When it goes to apply the memctx to actually create the commit, the file copy information is incomplete and loses the information for the files that shouldn't have been affected at all by the amend. Differential Revision: https://phab.mercurial-scm.org/D12625