Introduce Layout*::adjustVisualRectForRasterEffects and use it for SVG hairlines.

third_party/WebKit/LayoutTests/paint/invalidation/svg/repaint-stroke-width-changes-expected.txt

 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
         {
           "object": "LayoutSVGRect rect",
-          "rect": [10, 10, 460, 340],
+          "rect": [9, 9, 462, 342],
           "reason": "style change"
         },
         {
           "object": "LayoutSVGRoot svg",
           "rect": [10, 10, 460, 340],
           "reason": "bounds change"
         }
       ]
     }
   ],
   "objectPaintInvalidations": [
     {
       "object": "LayoutSVGRoot svg",
       "reason": "bounds change"
     },
     {
       "object": "LayoutSVGRect rect",
       "reason": "style change"
     }
   ]
 }