mac: Let remoting_host_prefpane link with libc++.

mac: Let remoting_host_prefpane link with libc++.

Once I figured out the static library libc++ build story, I'll likely move
this target back to libstdc++, but for now it works with libc++, so use the
libc++ in component build like every other target does.

See comment 7 on the linked bug for why the file in overrides/ is needed.

BUG=544531
Committed: https://crrev.com/bed1d0c35e86bc859f94573b4c15d18c17994383
Cr-Commit-Position: refs/heads/master@{#354824}

[Nico, 2015-10-18 04:56:30]

thakis@chromium.org changed reviewers:
+ lambroslambrou@chromium.org

[Lambros, 2015-10-19 17:47:05]

lgtm

[Nico, 2015-10-19 18:12:43]

The CQ bit was checked by thakis@chromium.org

[commit-bot: I haz the power, 2015-10-19 18:14:40]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1411553005/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1411553005/20001

[commit-bot: I haz the power, 2015-10-19 19:32:20]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-10-19 19:33:14]

Patchset 2 (id:??) landed as
https://crrev.com/bed1d0c35e86bc859f94573b4c15d18c17994383
Cr-Commit-Position: refs/heads/master@{#354824}