Turn test runner library into an actual component

Turn test runner library into an actual component

The main motivation is to enforce correct layering and dependencies

BUG=478250
R=jam@chromium.org

Committed: https://crrev.com/746754c581f8a0d0b6d1b9ec2256077391eed1b2
Cr-Commit-Position: refs/heads/master@{#333065}

[jochen (gone - plz use gerrit), 2015-06-05 12:01:19]

ptal

[jam, 2015-06-05 15:49:47]

lgtm

I can't tell from the cl description what is the reason for doing this though.
i.e. it seems the most important thing here is that this code isn't tied to
content; why does it matter if it's statically or dynamically linked in the
component build?

[jochen (gone - plz use gerrit), 2015-06-05 16:04:20]

it helped to get the dependencies right, for example

[jochen (gone - plz use gerrit), 2015-06-05 16:05:11]

The CQ bit was checked by jochen@chromium.org

[commit-bot: I haz the power, 2015-06-05 16:05:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1169493003/20001

[commit-bot: I haz the power, 2015-06-05 16:40:49]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-06-05 16:41:40]

Patchset 2 (id:??) landed as
https://crrev.com/746754c581f8a0d0b6d1b9ec2256077391eed1b2
Cr-Commit-Position: refs/heads/master@{#333065}