bluetooth: Layout tests for bluetooth error messages

bluetooth: Layout tests for bluetooth error messages

This is the third patch to add more descriptive error messages and
to return different errors based on the GATT Error:

 [1] http://crrev.com/1179733006
 [2] http://crrev.com/1177613002
 [3] This patch.


BUG=490419, 499542
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197149

[ortuno, 2015-06-09 23:34:41]

ortuno@chromium.org changed reviewers:
+ scheib@chromium.org

[ortuno, 2015-06-09 23:34:42]

@scheib: PTAL

[scheib, 2015-06-12 17:33:41]

LGTM

[ortuno, 2015-06-16 00:32:25]

The CQ bit was checked by ortuno@chromium.org

[ortuno, 2015-06-16 00:32:25]

The patchset sent to the CQ was uploaded after l-g-t-m from scheib@chromium.org
Link to the patchset: https://codereview.chromium.org/1164393004/#ps40001
(title: "Fix error message test since message on browser side changed.")

[commit-bot: I haz the power, 2015-06-16 00:32:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1164393004/40001

[commit-bot: I haz the power, 2015-06-16 00:35:43]

Committed patchset #3 (id:40001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197149