diff --stat: do not run diff on indentical files
diff --stat: do not run diff on indentical files

If two objects are known to be equal, there is no point running the diff.

Signed-off-by: Zbigniew Jędrzejewski-Szmek <1a002461b1932d3892b64879e6e8987274fa7074@in.waw.pl>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git