Fix getBBox() returning (0,0) bug when width or height is zero

LayoutTests/platform/linux/svg/clip-path/nested-clip-in-mask-path-based-clipping-expected.txt

Index: LayoutTests/platform/linux/svg/clip-path/nested-clip-in-mask-path-based-clipping-expected.txt
diff --git a/LayoutTests/svg/clip-path/nested-clip-in-mask-path-based-clipping-expected.txt b/LayoutTests/platform/linux/svg/clip-path/nested-clip-in-mask-path-based-clipping-expected.txt
similarity index 96%
copy from LayoutTests/svg/clip-path/nested-clip-in-mask-path-based-clipping-expected.txt
copy to LayoutTests/platform/linux/svg/clip-path/nested-clip-in-mask-path-based-clipping-expected.txt
index 9ba05b1ad863131b0172e29683e36d87268a0f6b..0cebf1ed048a52545bba7af2f9a8ec8895fe8d50 100644
--- a/LayoutTests/svg/clip-path/nested-clip-in-mask-path-based-clipping-expected.txt
+++ b/LayoutTests/platform/linux/svg/clip-path/nested-clip-in-mask-path-based-clipping-expected.txt
@@ -13,13 +13,13 @@ layer at (0,0) size 800x600
         RenderSVGEllipse {circle} at (0,0) size 2x2 [fill={[type=SOLID] [color=#000000]}] [cx=1.00] [cy=1.00] [r=0.50]
       RenderSVGResourceClipper {clipPath} [id="clip"] [clipPathUnits=objectBoundingBox]
         RenderSVGRect {rect} at (0,0) size 1x1 [fill={[type=SOLID] [color=#000000]}] [x=0.00] [y=0.00] [width=1.00] [height=1.00]
-          [clipPath="clip1"] RenderSVGResourceClipper {clipPath} at (-0.50,-0.50) size 1x1
+          [clipPath="clip1"] RenderSVGResourceClipper {clipPath} at (-1,-1) size 2x2
         RenderSVGRect {rect} at (0,0) size 1x1 [fill={[type=SOLID] [color=#000000]}] [x=0.00] [y=0.00] [width=1.00] [height=1.00]
-          [clipPath="clip2"] RenderSVGResourceClipper {clipPath} at (-0.50,0.50) size 1x1
+          [clipPath="clip2"] RenderSVGResourceClipper {clipPath} at (-1,0) size 2x2
         RenderSVGRect {rect} at (0,0) size 1x1 [fill={[type=SOLID] [color=#000000]}] [x=0.00] [y=0.00] [width=1.00] [height=1.00]
-          [clipPath="clip3"] RenderSVGResourceClipper {clipPath} at (0.50,-0.50) size 1x1
+          [clipPath="clip3"] RenderSVGResourceClipper {clipPath} at (0,-1) size 2x2
         RenderSVGRect {rect} at (0,0) size 1x1 [fill={[type=SOLID] [color=#000000]}] [x=0.00] [y=0.00] [width=1.00] [height=1.00]
-          [clipPath="clip4"] RenderSVGResourceClipper {clipPath} at (0.50,0.50) size 1x1
+          [clipPath="clip4"] RenderSVGResourceClipper {clipPath} at (0,0) size 2x2
       RenderSVGResourceMasker {mask} [id="mask1"] [maskUnits=objectBoundingBox] [maskContentUnits=objectBoundingBox]
         RenderSVGRect {rect} at (0,0) size 1x1 [fill={[type=SOLID] [color=#FFFFFF]}] [x=0.00] [y=0.00] [width=1.00] [height=1.00]
         RenderSVGRect {rect} at (0,0) size 1x1 [fill={[type=SOLID] [color=#000000]}] [x=0.00] [y=0.00] [width=1.00] [height=1.00]