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

Review URL: https://codereview.chromium.org/1237233002

Cr-Commit-Position: refs/heads/master@{#338880}