[CherryPick] new flexbox should ignore float set on flexitems

[CherryPick] new flexbox should ignore float set on flexitems

[Title] [CherryPick] new flexbox should ignore float set on flexitems
[Issue] TWEB-826
[Problem] WebAPI/W3C_CSS3/FlexibleBox/CSS3FlexBox_display_float.html test case failed.
[Cause] In the test case, the item in flexbox have float:right, but it should be disallowed.
[Solution] Cherry-pick the opensource patch.
[Cherry-Picker] KyungTae Kim <ktf.kim@samsung.com>

new flexbox should ignore float set on flexitems
https://bugs.webkit.org/show_bug.cgi?id=70792

Reviewed by Ojan Vafai.

Source/WebCore:

Force flex items to not float.

Test: css3/flexbox/floated-flexitem.html

* css/StyleResolver.cpp:
(WebCore::StyleResolver::adjustRenderStyle): Force NoFloat on flex items.

LayoutTests:

Make an example in the spec into a ref test.  Add some styles to make it a bit more clear what's happening.

* css3/flexbox/floated-flexitem-expected.html: Added.
* css3/flexbox/floated-flexitem.html: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@124064 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Change-Id: I1b17a729a10edc4d9cc9e74ab4e038630b1eadad