The type of LineSegment logicalLeft and logicalRight edges should not have been changed to LayoutUnit. They should be floats because all of the RenderBlockLineLayout calculations are based on floats for left,right values (vertical values are LayoutUnits). The mistake was pointed out and corrected in Blink, here: https://chromiumcodereview.appspot.com/14892005#msg6
Created attachment 228519 [details] Patch
Comment on attachment 228519 [details] Patch rs=me
Comment on attachment 228519 [details] Patch Clearing flags on attachment: 228519 Committed r166747: <http://trac.webkit.org/changeset/166747>
All reviewed patches have been landed. Closing bug.