Fix the bug that negative outline-offset is covered up by composited

third_party/WebKit/LayoutTests/compositing/overflow/overflow-scrollbar-layers-expected.txt

Index: third_party/WebKit/LayoutTests/compositing/overflow/overflow-scrollbar-layers-expected.txt
diff --git a/third_party/WebKit/LayoutTests/compositing/overflow/overflow-scrollbar-layers-expected.txt b/third_party/WebKit/LayoutTests/compositing/overflow/overflow-scrollbar-layers-expected.txt
index 417a0cedb36a62841fbd9acac49704bc7538a549..045c597de892a7a0a8409c1da2eca6f077cc0b8b 100644
--- a/third_party/WebKit/LayoutTests/compositing/overflow/overflow-scrollbar-layers-expected.txt
+++ b/third_party/WebKit/LayoutTests/compositing/overflow/overflow-scrollbar-layers-expected.txt
@@ -36,6 +36,11 @@
       "bounds": [15, 100]
     },
     {
+      "name": "Decoration Layer",
+      "bounds": [100, 100],
+      "drawsContent": true
+    },
+    {
       "name": "LayoutBlockFlow (positioned) DIV class='container'",
       "position": [8, 13],
       "bounds": [100, 100],
@@ -65,6 +70,11 @@
       "bounds": [100, 15]
     },
     {
+      "name": "Decoration Layer",
+      "bounds": [100, 100],
+      "drawsContent": true
+    },
+    {
       "name": "LayoutBlockFlow (positioned) DIV class='container'",
       "position": [8, 13],
       "bounds": [100, 100],
@@ -105,6 +115,11 @@
       "drawsContent": true
     },
     {
+      "name": "Decoration Layer",
+      "bounds": [100, 100],
+      "drawsContent": true
+    },
+    {
       "name": "LayoutBlockFlow (positioned) DIV class='container resizeWidget'",
       "position": [8, 13],
       "bounds": [100, 100],