[New Multicolumn] Add a drawing recorder for column rules.

LayoutTests/VirtualTestSuites

Index: LayoutTests/VirtualTestSuites
diff --git a/LayoutTests/VirtualTestSuites b/LayoutTests/VirtualTestSuites
index 204228ea4d3c4fbf57096a00815de0b6a8ce2157..c505b79ea5bc0911a11abcfcfccd66b269941d44 100644
--- a/LayoutTests/VirtualTestSuites
+++ b/LayoutTests/VirtualTestSuites
@@ -200,6 +200,11 @@
     "args": ["--enable-slimming-paint", "--enable-impl-side-painting"]
   },
   {
+    "prefix": "slimmingpaint",
+    "base": "fast/multicol",
+    "args": ["--enable-slimming-paint", "--enable-impl-side-painting", "--enable-region-based-columns"]
+  },
+  {
     "prefix": "rootlayerscrolls",
     "base": "fast/scrolling",
     "args": ["--root-layer-scrolls"]