Move RenderSVGContainer to layout/svg/LayoutSVGContainer.

LayoutTests/svg/custom/visibility-override-mask-expected.txt

Index: LayoutTests/svg/custom/visibility-override-mask-expected.txt
diff --git a/LayoutTests/svg/custom/visibility-override-mask-expected.txt b/LayoutTests/svg/custom/visibility-override-mask-expected.txt
index f6f97dcfa12215e909754860d1ad4250d648ad0c..2bbefa29cabbfd7f1ed836a788b85bc8630a6822 100644
--- a/LayoutTests/svg/custom/visibility-override-mask-expected.txt
+++ b/LayoutTests/svg/custom/visibility-override-mask-expected.txt
@@ -6,9 +6,9 @@ layer at (0,0) size 800x600
       LayoutSVGResourceMasker {mask} [id="mymask"] [maskUnits=objectBoundingBox] [maskContentUnits=userSpaceOnUse]
         RenderSVGRect {rect} at (0,0) size 100x100 [fill={[type=SOLID] [color=#FFFFFF]}] [x=0.00] [y=0.00] [width=100.00] [height=100.00]
     RenderSVGRect {rect} at (0,0) size 100x100 [fill={[type=SOLID] [color=#0000FF]}] [x=0.00] [y=0.00] [width=100.00] [height=100.00]
-    RenderSVGContainer {g} at (0,0) size 100x100
+    LayoutSVGContainer {g} at (0,0) size 100x100
       [masker="mymask"] LayoutSVGResourceMasker {mask} at (0,0) size 100x100
-      RenderSVGContainer {g} at (0,0) size 200x200
+      LayoutSVGContainer {g} at (0,0) size 200x200
         RenderSVGRect {rect} at (0,0) size 200x200 [fill={[type=SOLID] [color=#FF0000]}] [x=0.00] [y=0.00] [width=200.00] [height=200.00]
         RenderSVGRect {rect} at (0,0) size 100x100 [fill={[type=SOLID] [color=#008000]}] [x=0.00] [y=0.00] [width=100.00] [height=100.00]
       RenderSVGRect {rect} at (0,0) size 100x100 [fill={[type=SOLID] [color=#FF0000]}] [x=0.00] [y=0.00] [width=100.00] [height=100.00]