Add tools/mb to setup_links.py

Add tools/mb to setup_links.py

I believe this is needed in order to setup the iOS simulator bots
using the ios recipe module. We'll also most likely use MB in the future
when moving over from GYP to GN (since that's the sole purpose of the tool:
to make such a migration easier).

BUG=chromium:498746
NOTRY=True
TBR=phoglund@webrtc.org

Committed: https://crrev.com/68da769ab9579cac98fe4da7fb5da6dbb3842216
Cr-Commit-Position: refs/heads/master@{#11575}

[kjellander_webrtc, 2016-02-11 14:16:33]

The CQ bit was checked by kjellander@webrtc.org

[commit-bot: I haz the power, 2016-02-11 14:16:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1692543002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1692543002/1

[commit-bot: I haz the power, 2016-02-11 14:18:20]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-02-11 14:18:26]

Description was changed from

==========
Add tools/mb to setup_links.py

I believe this is needed in order to setup the iOS simulator bots
using the ios recipe module. We'll also most likely use MB in the future
when moving over from GYP to GN (since that's the sole purpose of the tool:
to make such a migration easier).

BUG=chromium:498746
NOTRY=True
TBR=phoglund@webrtc.org
==========

to

==========
Add tools/mb to setup_links.py

I believe this is needed in order to setup the iOS simulator bots
using the ios recipe module. We'll also most likely use MB in the future
when moving over from GYP to GN (since that's the sole purpose of the tool:
to make such a migration easier).

BUG=chromium:498746
NOTRY=True
TBR=phoglund@webrtc.org

Committed: https://crrev.com/68da769ab9579cac98fe4da7fb5da6dbb3842216
Cr-Commit-Position: refs/heads/master@{#11575}
==========

[commit-bot: I haz the power, 2016-02-11 14:18:27]

Patchset 1 (id:??) landed as
https://crrev.com/68da769ab9579cac98fe4da7fb5da6dbb3842216
Cr-Commit-Position: refs/heads/master@{#11575}

[kjellander_webrtc, 2016-02-11 14:36:21]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.webrtc.org/1691723003/ by kjellander@webrtc.org.

The reason for reverting is: Doesn't solve the problem and MB is actually
hardcoded to use gyp_chromium when running in GYP mode, so it's better to clean
this up for now..