[CSS Regions] Add performance tests
https://bugs.webkit.org/show_bug.cgi?id=113303

Reviewed by Antti Koivisto.

Add simple performance tests for regions, without nested named flows: a region chain and a flow article.
The regions.js script is used to generate the tests and can set the following parameters: the number of regions,
the number of paragraphs, the regions width, height, max-height and the propability of a forced break after a paragraph.

The tests are skipped for now. They should be enabled once the regions performance is stable enough to create a baseline.

* Layout/RegionsAuto.html: Added. A few regions with a short article. The regions have auto-height and some
paragraphs (80%) have forced breaks after. Stress test for the auto-height algorithm.
* Layout/RegionsAutoMaxHeight.html: Added. A lot of regions with auto-height and max-height. Tests the impact of
max-height on the auto-height algorithm.
* Layout/RegionsFixed.html: Added. A lot of regions with a long article. Some paragraphs (50%) have forced breaks after.
Stress test for the regions layout algorithm.
* Layout/RegionsFixedShort.html: Added. A lot of short regions with a long content. Tests the impact of unforced breaks
on the layout speed.
* Layout/resources/regions.css: Added.
(.articleInFlow):
(.articleNone):
(.region):
(.contentParagraph):
(.breakAfter):
(.regionContainer):
* Layout/resources/regions.js: Added.
(.):
* Skipped:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@147214 268f45cc-cd09-0410-ab3c-d52691b4dbfc
[Qt] Removal of misplaced stuff after r146692.

* platform/qt-unknown/fast/text/international/text-spliced-font-expected.png: Removed.
* platform/qt-unknown/svg/carto.net/tabgroup-expected.png: Removed.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@147215 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Unreviewed Mac gardening.

* platform/mac/fast/events/event-attribute-expected.txt: Added.
New baseline after r147205.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@147216 268f45cc-cd09-0410-ab3c-d52691b4dbfc