DevTools: [Console] fix selection of all console messages

DevTools: [Console] fix selection of all console messages

It turns out that selection of all elements in console (aka Ctrl-A)
works properly only if the last element in viewport DOM is a block
element with some text.

BUG=410899
R=vsevik

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=181850

[lushnikov, 2014-09-11 17:01:55]

Please, take a look

For future reference: the culprit in WebCore seems to be hidden somewhere
between calls to Position::isCandidate and VisiblePosition::canonicalPosition.

[vsevik, 2014-09-11 18:44:11]

lgtm

Is it possible to reproduce this in older versions by opening the modern remote
debugging front-end there? can we bisect this way?

[lushnikov, 2014-09-11 18:52:44]

Sure, to the extent of support of some "modern" features we use in the front-end
(e.g. flex)

I feel like it might have never been working properly.

[lushnikov, 2014-09-11 18:53:24]

The CQ bit was checked by lushnikov@chromium.org

[commit-bot: I haz the power, 2014-09-11 18:53:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/564893002/1

[commit-bot: I haz the power, 2014-09-11 20:58:48]

Committed patchset #1 (id:1) as 181850