DevTools: [CodeMirror] handle new-lines in error popovers

DevTools: [CodeMirror] handle new-lines in error popovers

Add support to new-line character handling in error and warning console
message texts which are shown in a popover in editor.

BUG=404380
R=vsevik

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=180413

[lushnikov, 2014-08-16 18:16:00]

ptal

[vsevik, 2014-08-16 22:04:00]

lgtm

[lushnikov, 2014-08-16 23:16:06]

On 2014/08/16 22:04:00, vsevik wrote:
> lgtm

midnight lgtm :)

[lushnikov, 2014-08-16 23:16:09]

The CQ bit was checked by lushnikov@chromium.org

[commit-bot: I haz the power, 2014-08-16 23:16:55]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/lushnikov@chromium.org/478963002/1

[commit-bot: I haz the power, 2014-08-17 00:18:05]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  linux_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/linux_gpu_trigger...)

[commit-bot: I haz the power, 2014-08-17 00:44:24]

Committed patchset #1 (1) as 180413