Enable slimming paint for fast/repaint

LayoutTests/platform/linux/fast/repaint/crbug-371640-expected.txt

Index: LayoutTests/platform/linux/fast/repaint/crbug-371640-expected.txt
diff --git a/LayoutTests/platform/linux/fast/repaint/crbug-371640-expected.txt b/LayoutTests/platform/linux/fast/repaint/crbug-371640-expected.txt
index c628a9addc823f156cf1e3a498155b3cb7d0a8c5..a7ec8b8e82015dac609b89d10e747c77497cdcd1 100644
--- a/LayoutTests/platform/linux/fast/repaint/crbug-371640-expected.txt
+++ b/LayoutTests/platform/linux/fast/repaint/crbug-371640-expected.txt
@@ -22,6 +22,21 @@
         [88, 88, 100, 100],
         [88, 88, 100, 100],
         [88, 88, 4, 19]
+      ],
+      "paintInvalidationClients": [
+        "InlineTextBox '\u00A0'",
+        "LayoutText #text",
+        "RootInlineBox",
+        "LayoutBlockFlow DIV id='to_remove' class='item'",
+        "LayoutBlockFlow (relative positioned) (floating) DIV id='to_remove_inner' class='inner'",
+        "LayoutBlockFlow (floating) DIV id='node' class='outer'",
+        "LayoutBlockFlow (floating) DIV id='container'",
+        "LayoutBlockFlow (floating) DIV id='keep_outer' class='outer'",
+        "LayoutBlockFlow (relative positioned) (floating) DIV id='keep_inner' class='inner'",
+        "LayoutBlockFlow (positioned) DIV class='abs_pos'",
+        "LayoutBlockFlow DIV id='keep' class='item'",
+        "LayoutText #text",
+        "InlineTextBox '\u00A0'"
       ]
     }
   ]