Merge 129370 - snapToSize rounds the incorrectly for negative locations

LayoutTests/platform/mac-wk2/Skipped

 #
 # Copyright (C) 2010 Apple Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
 # are met:
 #
 # 1.  Redistributions of source code must retain the above copyright
 #     notice, this list of conditions and the following disclaimer. 
 # 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 199 matching lines @@
 fast/sub-pixel/inline-block-with-margin.html
 fast/sub-pixel/inline-block-with-padding.html
 fast/sub-pixel/large-sizes.html
 fast/sub-pixel/layout-boxes-with-zoom.html
 fast/sub-pixel/position-right-aligns-with-container.html
 fast/sub-pixel/selection/selection-gaps-at-fractional-offsets.html
 fast/sub-pixel/size-of-box-with-zoom.html
 fast/sub-pixel/table-rows-no-gaps.html
 fast/sub-pixel/sub-pixel-accumulates-to-layers.html
 fast/sub-pixel/selection/selection-rect-in-sub-pixel-table.html
+fast/sub-pixel/snap-negative-location.html
 
 # fast/events/pagehide-timeout.html, pageshow-pagehide-on-back-cached-with-frames.html, and
 # pageshow-pagehide-on-back-cached.html flakey on Lion Intel Debug WebKit testers.
 # https://bugs.webkit.org/show_bug.cgi?id=81291
 fast/events/pagehide-timeout.html
 fast/events/pageshow-pagehide-on-back-cached-with-frames.html
 fast/events/pageshow-pagehide-on-back-cached.html
 
 # [WK2] http/tests/navigation/https-in-page-cache.html times out on mac-wk2
 # https://bugs.webkit.org/show_bug.cgi?id=81622
@@ skipping 156 matching lines @@
 ########################################
 
 
 ###### This file has four sections. When adding new tests, make sure to
 ###### add to the right section:
 
 ### (1) Classified failures with bug reports
 ### (2) Classified failures without bug reports (yet)
 ### (3) Unclassified failures
 ### (4) Features that are not supported in WebKit2 and likely never will be