https://bugs.webkit.org/show_bug.cgi?id=91410

Reviewed by Eric Seidel.

Source/WebCore: 

At certain zoom levels a rounding error in the table layout code cases
the table background color to bleed through between cells. Tables layout
happens on pixel bounds however the paint offset wasn't correctly rounded.

Test: fast/sub-pixel/table-rows-no-gaps.html

* rendering/RenderTable.cpp:
(WebCore::RenderTable::paintObject):
Round paintOffset before passing it to the paint method of the children.

LayoutTests: 

Add test to ensure that the table background color doesn't bleed through
when the table and a cell are positioned on a subpixel bound.

* fast/sub-pixel/table-rows-no-gaps-expected.html: Added.
* fast/sub-pixel/table-rows-no-gaps.html: Added.
* platform/chromium-linux/css1/basic/inheritance-expected.png:
* platform/chromium-linux/plugins/embed-attributes-style-expected.png:
* platform/chromium-linux/svg/zoom/page/zoom-img-preserveAspectRatio-support-1-expected.png:
* platform/chromium-linux/svg/zoom/page/zoom-replaced-intrinsic-ratio-001-expected.png:
* platform/chromium-linux/svg/zoom/page/zoom-svg-through-object-with-absolute-size-2-expected.png:
* platform/chromium-linux/svg/zoom/page/zoom-svg-through-object-with-absolute-size-expected.png:
* platform/chromium-linux/svg/zoom/page/zoom-svg-through-object-with-percentage-size-expected.png:
* platform/chromium-linux/tables/mozilla/bugs/bug73321-expected.png:
Updated expectations to match new rounding logic. The new results better
match the rendering prior to turning on subpixel layout.
        
* platform/efl/Skipped:
* platform/mac-lion/Skipped:
* platform/mac-snowleopard/Skipped:
* platform/mac-wk2/Skipped:
* platform/mac/Skipped:
* platform/qt-4.8/Skipped:
* platform/qt/Skipped:
* platform/win-wk2/Skipped:
* platform/win-xp/Skipped:
* platform/win/Skipped:
* platform/wincairo/Skipped:
* platform/wk2/Skipped:
Mark new test as skipped on platforms that have not enabled subpixel
layout.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@122769 268f45cc-cd09-0410-ab3c-d52691b4dbfc