https://bugs.webkit.org/show_bug.cgi?id=124919

Source/WebCore:

Relative positioned elements have self-painting layers that don't propagate the visual overflow
so the layer's position should be used when determining the clipping rectangle for box decorations.

Reviewed by Mihnea Ovidenie.

Test: fast/regions/relative-borders-overflow.html

* rendering/RenderFlowThread.cpp:
(WebCore::RenderFlowThread::decorationsClipRectForBoxInRegion):

LayoutTests:

Added new tests for correct painting of the borders of a relatively positioned element inside a region.

Reviewed by Mihnea Ovidenie.

* fast/regions/relative-borders-overflow-expected.html: Added.
* fast/regions/relative-borders-overflow.html: Added.
* fast/regions/relative-in-absolute-borders-overflow-expected.html: Added.
* fast/regions/relative-in-absolute-borders-overflow.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@160014 268f45cc-cd09-0410-ab3c-d52691b4dbfc