delta-find: move final debug processing in a `_dbg_process_data` method

This will help us making sure we can call the necessary debugging code in
alternative codepath.

mercurial/revlogutils/deltas.py

@@ -1471,7 +1471,10 b' class deltacomputer:'
                 if target_key:
                     target_revlog += b'%s:' % target_key
             dbg['target-revlog'] = target_revlog
+            self._dbg_process_data(dbg)
+        return deltainfo
 
+    def _dbg_process_data(self, dbg):
             if self._debug_info is not None:
                 self._debug_info.append(dbg)
 
@@ -1505,7 +1508,6 b' class deltacomputer:'
                     dbg["duration"],
                 )
                 self._write_debug(msg)
-        return deltainfo
 
 
 def delta_compression(default_compression_header, deltainfo):