Don't force full invalidation on padding or margin change

LayoutTests/fast/repaint/padding-margin-expected.txt

Index: LayoutTests/fast/repaint/padding-margin-expected.txt
diff --git a/LayoutTests/fast/repaint/padding-margin-expected.txt b/LayoutTests/fast/repaint/padding-margin-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..205227ead98a00b51c9c3858e8e194b371449aa9
--- /dev/null
+++ b/LayoutTests/fast/repaint/padding-margin-expected.txt
@@ -0,0 +1,33 @@
+{
+  "bounds": [800, 600],
+  "children": [
+    {
+      "bounds": [800, 600],
+      "contentsOpaque": true,
+      "drawsContent": true,
+      "repaintRects": [
+        [300, 150, 40, 140],
+        [220, 470, 60, 60],
+        [220, 320, 60, 60],
+        [220, 320, 60, 60],
+        [220, 170, 100, 100],
+        [220, 20, 100, 100],
+        [220, 20, 100, 100],
+        [200, 450, 100, 100],
+        [200, 300, 100, 100],
+        [200, 300, 100, 100],
+        [200, 250, 140, 40],
+        [200, 150, 100, 100],
+        [200, 0, 100, 100],
+        [200, 0, 100, 100],
+        [100, 150, 40, 140],
+        [20, 320, 60, 60],
+        [20, 20, 100, 100],
+        [0, 300, 100, 100],
+        [0, 250, 140, 40],
+        [0, 0, 100, 100]
+      ]
+    }
+  ]
+}
+