Allow tab model to be selected during merge if current model has no tabs

Allow tab model to be selected during merge if current model has no tabs

On tablets it's possible to end up with a "dummy" tab selected if the
EmptyBackgroundView is showing when a merge is triggered and the currently
"selected" model has no tabs in it. In this case, do not reset
the tab model selection to the model that was selected before the merge.

BUG=644707
Committed: https://crrev.com/b7c7b6b79243f0e1bc330e2df22cbfb1bb008a35
Cr-Commit-Position: refs/heads/master@{#417145}

[Theresa, 2016-09-08 00:19:48]

The CQ bit was checked by twellington@chromium.org to run a CQ dry run

[Theresa, 2016-09-08 00:20:13]

twellington@chromium.org changed reviewers:
+ dfalcantara@chromium.org

[Theresa, 2016-09-08 00:20:13]

ptal

[commit-bot: I haz the power, 2016-09-08 00:20:16]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[gone, 2016-09-08 00:25:58]

So many fun special cases here.

lgtm

[Theresa, 2016-09-08 00:31:23]

The CQ bit was unchecked by twellington@chromium.org

[Theresa, 2016-09-08 00:31:23]

The CQ bit was checked by twellington@chromium.org

[commit-bot: I haz the power, 2016-09-08 00:31:49]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-09-08 01:19:14]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-09-08 01:21:42]

Description was changed from

==========
Allow tab model to be selected during merge if current model has no tabs

On tablets it's possible to end up with a "dummy" tab selected if the
EmptyBackgroundView is showing when a merge is triggered and the currently
"selected" model has no tabs in it. In this case, do not reset
the tab model selection to the model that was selected before the merge.

BUG=644707
==========

to

==========
Allow tab model to be selected during merge if current model has no tabs

On tablets it's possible to end up with a "dummy" tab selected if the
EmptyBackgroundView is showing when a merge is triggered and the currently
"selected" model has no tabs in it. In this case, do not reset
the tab model selection to the model that was selected before the merge.

BUG=644707

Committed: https://crrev.com/b7c7b6b79243f0e1bc330e2df22cbfb1bb008a35
Cr-Commit-Position: refs/heads/master@{#417145}
==========

[commit-bot: I haz the power, 2016-09-08 01:21:43]

Patchset 1 (id:??) landed as
https://crrev.com/b7c7b6b79243f0e1bc330e2df22cbfb1bb008a35
Cr-Commit-Position: refs/heads/master@{#417145}