Reland #1: mac: Migrate xibs to OSX 10.9.5, Xcode 5.1.1.

Reland #1: mac: Migrate xibs to OSX 10.9.5, Xcode 5.1.1.

The original CL failed to land because some of the WebKit testers were also
building on OSX 10.6 and OSX 10.8. Those tests have been updated to no longer
build.

> To generate this change, I ran the command "find . -name *\.xib | grep -v
> third_party | xargs open". For each file, I changed "Opens in" to "Xcode 5.1"
> and "Builds for" to "OS X 10.6 and Later".
>
> I ran this process twice and diffed the results to ensure that I didn't
> accidentally change any of the xibs in an unintended fashion.
>
> BUG=327347
>
> Committed: https://crrev.com/38fadb859b666d05a0cbbc39e154c81d637540ac
> Cr-Commit-Position: refs/heads/master@{#337501}

TBR=rsesek@chromium.org,garykac@chromium.org,avi@chromium.org,dcaiafa@chromium.org
BUG=327347
Committed: https://crrev.com/3c914071e894022981c7f4c525aa7431260cbbb1
Cr-Commit-Position: refs/heads/master@{#338880}

[erikchen, 2015-07-15 17:09:18]

The CQ bit was checked by erikchen@chromium.org

[commit-bot: I haz the power, 2015-07-15 17:10:13]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1237233002/1

[commit-bot: I haz the power, 2015-07-15 17:49:57]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-07-15 17:51:42]

Patchset 1 (id:??) landed as
https://crrev.com/3c914071e894022981c7f4c525aa7431260cbbb1
Cr-Commit-Position: refs/heads/master@{#338880}