Merge branch 'jk/pack-objects-reports-num-objects-to-trace2'

The "git pack-objects" command learned to report the number of
objects it packed via the trace2 mechanism.

* jk/pack-objects-reports-num-objects-to-trace2:
  pack-objects: write objects packed to trace2
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 2d9a3bd..d7743f1 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -964,6 +964,8 @@
 	if (written != nr_result)
 		die(_("wrote %"PRIu32" objects while expecting %"PRIu32),
 		    written, nr_result);
+	trace2_data_intmax("pack-objects", the_repository,
+			   "write_pack_file/wrote", nr_result);
 }
 
 static int no_try_delta(const char *path)