Update baselines for some svg/custom/ tests

LayoutTests/svg/custom/js-update-gradient-expected.txt

Index: LayoutTests/svg/custom/js-update-gradient-expected.txt
diff --git a/LayoutTests/svg/custom/js-update-gradient-expected.txt b/LayoutTests/svg/custom/js-update-gradient-expected.txt
index fbb9cc5411399f8fc936343a9b4edc883a7d1206..e0e5ad3ab2d7b81599ef574c6534f4774d8f0f1d 100644
--- a/LayoutTests/svg/custom/js-update-gradient-expected.txt
+++ b/LayoutTests/svg/custom/js-update-gradient-expected.txt
@@ -1,15 +1,15 @@
-(GraphicsLayer
-  (bounds 800.00 600.00)
-  (children 1
-    (GraphicsLayer
-      (bounds 800.00 600.00)
-      (contentsOpaque 1)
-      (drawsContent 1)
-      (repaint rects
-        (rect 10.00 10.00 430.00 80.00)
-        (rect 10.00 100.00 430.00 80.00)
-      )
-    )
-  )
-)
+{
+  "bounds": [800, 600],
+  "children": [
+    {
+      "bounds": [800, 600],
+      "contentsOpaque": true,
+      "drawsContent": true,
+      "repaintRects": [
+        [10, 100, 430, 80],
+        [10, 10, 430, 80]
+      ]
+    }
+  ]
+}