offsetWidth/height incorrect for images when zoomed
https://bugs.webkit.org/show_bug.cgi?id=106624

Source/WebCore:

Reviewed by Levi Weintraub.

offsetWidth and height are incorrect for images at certain zoom
levels due to flooring the values ones adjusted for zoom.
By rounding the value instead we avoid the problem and return
the right size.

Test: fast/images/zoomed-offset-size.html

* dom/Element.cpp:
(WebCore::Element::offsetWidth):
(WebCore::Element::offsetHeight):
(WebCore::Element::clientWidth):
(WebCore::Element::clientHeight):
Change to round (as opposed to floor) the zoom adjusted value.

* rendering/RenderObject.h:
(WebCore::adjustLayoutUnitForAbsoluteZoom):
* rendering/style/RenderStyle.h:
(WebCore::adjustLayoutUnitForAbsoluteZoom):
Add LayoutUnit version of adjustForAbsoluteZoom to avoid float
conversion.

LayoutTests:

Reviewed by Levi Weintraub.

Add test for offsetWidth/Height for zoomed image.

* fast/images/zoomed-offset-size-expected.txt: Added.
* fast/images/zoomed-offset-size.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@139537 268f45cc-cd09-0410-ab3c-d52691b4dbfc