Update Media Router button style.

Update Media Router button style.

This change removes the margin on either side of buttons in the Media Router WebUI.

Committed: https://crrev.com/dffcddad62c7dfb224af0e96f80a0609062db356
Cr-Commit-Position: refs/heads/master@{#330268}

[apacible, 2015-05-15 22:31:09]

apacible@chromium.org changed reviewers:
+ wez@chromium.org

[apacible, 2015-05-15 22:31:24]

PTAL, thanks!

[Wez, 2015-05-15 23:33:12]

CL descriptions should give the reader context for _what_ the change is, and
_why_ it's needed (and, if they're super complex, _how_, although I'd argue that
belongs in the code comments ;) - can you provide a more helpful description?

#tinycodereviewbikeshed

[apacible, 2015-05-15 23:42:58]

Updated, and some screenshots:

Route Details:
- Before: https://screenshot.googleplex.com/DPVhkLWCgkB.png
- After: https://screenshot.googleplex.com/rySAQ1U8WGR.png

Issue:
- Before: https://screenshot.googleplex.com/kQQW66FCBNX.png
- After: https://screenshot.googleplex.com/sqqtU3dhZo1.png

[Wez, 2015-05-16 00:17:51]

lgtm

[apacible, 2015-05-16 00:43:51]

The CQ bit was checked by apacible@chromium.org

[commit-bot: I haz the power, 2015-05-16 00:44:26]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1133283005/1

[commit-bot: I haz the power, 2015-05-16 02:08:01]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-18 11:31:00]

Patchset 1 (id:??) landed as
https://crrev.com/dffcddad62c7dfb224af0e96f80a0609062db356
Cr-Commit-Position: refs/heads/master@{#330268}