Don't pixel snap for ellipsis

LayoutTests/platform/mac/css1/box_properties/padding_right-expected.txt

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       RenderBlock {P} at (0,0) size 769x18
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           text run at (0,0) width 355: "The style declarations which apply to the text below are:"
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         RenderText {#text} at (0,0) size 576x90
@@ skipping 28 matching lines @@
           text run at (386,18) width 358: "The text has been right-aligned in order to make the right"
           text run at (609,36) width 135: "padding easier to see."
       RenderBlock {P} at (0,329) size 769x54 [bgcolor=#00FFFF]
         RenderText {#text} at (36,0) size 674x54
           text run at (36,0) width 599: "This element should have a right padding of 5 em, which will require extra text in order to test. "
           text run at (635,0) width 54: "Both the"
           text run at (15,18) width 410: "content background and the padding should be aqua (light blue). "
           text run at (425,18) width 264: "The text has been right-aligned in order to"
           text run at (460,36) width 229: "make the right padding easier to see."
       RenderBlock {P} at (0,399) size 769x54 [bgcolor=#00FFFF]
-        RenderText {#text} at (19,0) size 574x54
-          text run at (19,0) width 557: "This element should have a right padding of 25%, which is calculated with respect to the"
-          text run at (9,18) width 180: "width of the parent element. "
-          text run at (189,18) width 387: "Both the content background and the padding should be aqua"
-          text run at (2,36) width 77: "(light blue). "
-          text run at (79,36) width 497: "The text has been right-aligned in order to make the right padding easier to see."
+        RenderText {#text} at (19,0) size 575x54
+          text run at (19,0) width 558: "This element should have a right padding of 25%, which is calculated with respect to the"
+          text run at (9,18) width 181: "width of the parent element. "
+          text run at (189,18) width 388: "Both the content background and the padding should be aqua"
+          text run at (2,36) width 78: "(light blue). "
+          text run at (79,36) width 498: "The text has been right-aligned in order to make the right padding easier to see."
       RenderBlock {UL} at (0,469) size 769x72 [bgcolor=#808080]
         RenderListItem {LI} at (40,0) size 704x36
           RenderListMarker at (-17,0) size 7x18: bullet
           RenderText {#text} at (7,0) size 697x36
             text run at (7,0) width 697: "The right padding on this unordered list has been set to 25 pixels, which will require some extra text in order to"
             text run at (679,18) width 25: "test."
         RenderListItem {LI} at (40,36) size 704x36 [bgcolor=#FFFFFF]
           RenderListMarker at (-17,0) size 7x18: bullet
           RenderText {#text} at (19,0) size 660x36
             text run at (19,0) width 660: "This list item has a right padding of 25 pixels, which will appear to the left of the gray padding of the UL"
@@ skipping 35 matching lines @@
                   text run at (420,18) width 302: "The text has been right-aligned in order to make"
                   text run at (531,36) width 191: "the right padding easier to see."
               RenderBlock {P} at (4,178) size 747x54 [bgcolor=#00FFFF]
                 RenderText {#text} at (14,0) size 658x54
                   text run at (14,0) width 599: "This element should have a right padding of 5 em, which will require extra text in order to test. "
                   text run at (613,0) width 54: "Both the"
                   text run at (9,18) width 410: "content background and the padding should be aqua (light blue). "
                   text run at (419,18) width 248: "The text has been right-aligned in order"
                   text run at (422,36) width 245: "to make the right padding easier to see."
               RenderBlock {P} at (4,248) size 747x72 [bgcolor=#00FFFF]
-                RenderText {#text} at (3,0) size 557x72
-                  text run at (3,0) width 557: "This element should have a right padding of 25%, which is calculated with respect to the"
-                  text run at (27,18) width 180: "width of the parent element. "
-                  text run at (207,18) width 353: "Both the content background and the padding should be"
-                  text run at (36,36) width 111: "aqua (light blue). "
-                  text run at (147,36) width 413: "The text has been right-aligned in order to make the right padding"
-                  text run at (480,54) width 80: "easier to see."
+                RenderText {#text} at (3,0) size 558x72
+                  text run at (3,0) width 558: "This element should have a right padding of 25%, which is calculated with respect to the"
+                  text run at (27,18) width 181: "width of the parent element. "
+                  text run at (207,18) width 354: "Both the content background and the padding should be"
+                  text run at (36,36) width 112: "aqua (light blue). "
+                  text run at (147,36) width 414: "The text has been right-aligned in order to make the right padding"
+                  text run at (480,54) width 81: "easier to see."
               RenderBlock {UL} at (4,336) size 747x72 [bgcolor=#808080]
                 RenderListItem {LI} at (40,0) size 682x36
                   RenderListMarker at (-17,0) size 7x18: bullet
                   RenderText {#text} at (1,0) size 681x36
                     text run at (1,0) width 681: "The right padding on this unordered list has been set to 25 pixels, which will require some extra text in order"
                     text run at (641,18) width 41: "to test."
                 RenderListItem {LI} at (40,36) size 682x36 [bgcolor=#FFFFFF]
                   RenderListMarker at (-17,0) size 7x18: bullet
                   RenderText {#text} at (23,0) size 634x36
                     text run at (23,0) width 634: "This list item has a right padding of 25 pixels, which will appear to the left of the gray padding of the"
                     text run at (578,18) width 79: "UL element."
               RenderBlock {P} at (4,424) size 747x54 [bgcolor=#00FFFF]
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                   text run at (69,0) width 574: "This element should have no right padding, since negative padding values are not allowed. "
                   text run at (643,0) width 104: "Both the content"
                   text run at (14,18) width 408: "background and the normal padding should be aqua (light blue). "
                   text run at (422,18) width 325: "The text has been right-aligned in order to make the"
                   text run at (532,36) width 215: "lack of right padding easier to see."