Simplify 'position' adjustment of top layer elements

Simplify 'position' adjustment of top layer elements

Previously, we adjusted 'position' and 'display' for top layer
elements. There is already code to adjust the 'display' of positioned
elements, using equivalentBlockDisplay. This commit moves top layer
element adjustment above that code, so we don't have to set display
separately.

Also, convert the relevant layout tests from ref-tests to check-layout
tests, as they are just testing position.

BUG=140205
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=151903

[falken, 2013-06-06 05:11:50]

Morita-san, could you please review?

[Hajime Morrita, 2013-06-06 05:18:55]

lgtm.

[commit-bot: I haz the power, 2013-06-06 05:22:33]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/falken@chromium.org/16529003/1

[commit-bot: I haz the power, 2013-06-06 06:31:48]

Retried try job too often on linux_layout_rel for step(s) webkit_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=linux_layo...

[commit-bot: I haz the power, 2013-06-06 07:22:43]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/falken@chromium.org/16529003/1

[commit-bot: I haz the power, 2013-06-06 08:44:40]

Change committed as 151903