imap: use git-cat-file asynchronously

This ought to improve overall performance with multiple clients.
Single client performance suffers a tiny bit due to extra
syscall overhead from epoll.

This also makes the existing async interface easier-to-use,
since calling cat_async_begin is no longer required.

1 files changed, 0 insertions, 1 deletions

diff --git a/xt/cmp-msgstr.t b/xt/cmp-msgstr.t
index 6bae0f66..0276f845 100644
--- a/xt/cmp-msgstr.t
+++ b/xt/cmp-msgstr.t
@@ -93,7 +93,6 @@ my $git_cb = sub {
                 diag xqx([qw(git diff), "$tmpdir/mime", "$tmpdir/eml"]);
         }
 };
-$git->cat_async_begin;
 my $t = timeit(1, sub {
         while (<$fh>) {
                 my ($oid, $type) = split / /;