Only use web app frame for bookmark apps.

Only use web app frame for bookmark apps.

The web app frame is experimental and should only be used by bookmark
apps.

This change also moves tests for bookmark app browser functionality out
of the general browser browser tests file into a separate file.

BUG=368372
Committed: https://crrev.com/75bd9665feeb61f650bce70a52f8773c2a800cd7
Cr-Commit-Position: refs/heads/master@{#322435}

[benwells, 2015-03-26 07:47:52]

benwells@chromium.org changed reviewers:
+ thestig@chromium.org

[benwells, 2015-03-26 07:47:52]

Note I'll be moving all the bookmark app stuff out of browser.cc in a follow up
patch.

[Lei Zhang, 2015-03-26 18:27:51]

The CQ bit was checked by thestig@chromium.org

[Lei Zhang, 2015-03-26 18:27:51]

lgtm

[commit-bot: I haz the power, 2015-03-26 18:28:32]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1037003002/1

[commit-bot: I haz the power, 2015-03-26 18:32:57]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-26 18:33:54]

Patchset 1 (id:??) landed as
https://crrev.com/75bd9665feeb61f650bce70a52f8773c2a800cd7
Cr-Commit-Position: refs/heads/master@{#322435}