commitctx: move `writechangesetcopy` business at the end a code section

This code is to handle a specific subcase so we move it a the end. This allow
to gather the rest of the "core" code closer to the related logic.

mercurial/commit.py

@@ -138,12 +138,12 b' def commitctx(repo, ctx, error=False, or'
 
             touched.extend(removed)
 
+            files = touched
+            mn = _commit_manifest(tr, linkrev, ctx, mctx, files, added, drop)
+
             if writechangesetcopy:
                 filesremoved = removed
 
-            files = touched
-            mn = _commit_manifest(tr, linkrev, ctx, mctx, files, added, drop)
-
         if not writefilecopymeta:
             # If writing only to changeset extras, use None to indicate that
             # no entry should be written. If writing to both, write an empty