[PATCH 3 of 5] httpclient: use absolute_import

[Yuya Nishihara]

On Wed, 23 Dec 2015 12:46:45 -0800, Gregory Szorc wrote:
> # HG changeset patch
> # User Gregory Szorc <gregory.szorc at gmail.com>
> # Date 1450763693 28800
> #      Mon Dec 21 21:54:53 2015 -0800
> # Node ID 99f6ec7e804f0b637bae81a7228b4d8a88ae6eac
> # Parent  9784529187b73667791ca5c0f911c6460acd3b4d
> httpclient: use absolute_import

IIRC, httpclient is vendor code. I'm not certain if we should modify it.
Augie, can you take a look?