Enable slimming paint for fast/repaint

LayoutTests/fast/repaint/multicol-as-paint-container-expected.txt

Index: LayoutTests/fast/repaint/multicol-as-paint-container-expected.txt
diff --git a/LayoutTests/fast/repaint/multicol-as-paint-container-expected.txt b/LayoutTests/fast/repaint/multicol-as-paint-container-expected.txt
index cd70482307b3c358f9652dca4de3ab9d59a7a4fc..211daa74d1e86453952cdf5b7f9ddbcf13be8f25 100644
--- a/LayoutTests/fast/repaint/multicol-as-paint-container-expected.txt
+++ b/LayoutTests/fast/repaint/multicol-as-paint-container-expected.txt
@@ -14,6 +14,27 @@
           "repaintRects": [
             [0, 0, 630, 180],
             [0, 0, 625, 180]
+          ],
+          "paintInvalidationClients": [
+            "LayoutText #text",
+            "InlineTextBox 'Lorem ipsum'",
+            "InlineTextBox 'dolor sit amet,'",
+            "InlineTextBox 'consectetur'",
+            "InlineTextBox 'adipiscing'",
+            "InlineTextBox 'elit. Fusce'",
+            "InlineTextBox 'varius, metus'",
+            "InlineTextBox 'eu fringilla'",
+            "InlineTextBox 'pulvinar, ipsum'",
+            "InlineTextBox 'sapien'",
+            "InlineTextBox 'ultricies arcu,'",
+            "InlineTextBox 'non condimentum'",
+            "InlineTextBox 'quam est eu'",
+            "InlineTextBox 'purus. Ut nisl'",
+            "InlineTextBox 'libero,'",
+            "InlineTextBox 'suscipit ut leo'",
+            "InlineTextBox 'eget, dapibus'",
+            "InlineTextBox 'ultrices dolor.'",
+            "LayoutMultiColumnSet (anonymous)"
           ]
         }
       ]