Turn on CompositeOpaqueFixedPosition for test and rebase tests.

third_party/WebKit/LayoutTests/compositing/rtl/rtl-iframe-fixed-overflow-scrolled-expected.txt

 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true
     },
     {
       "name": "LayoutIFrame (positioned) IFRAME",
@@ skipping 17 matching lines @@
       "position": [-615, 0],
       "bounds": [1000, 1000]
     },
     {
       "name": "LayoutView #document",
       "bounds": [1000, 1000],
       "drawsContent": true,
       "backgroundColor": "#FF0000"
     },
     {
+      "name": "LayoutBlockFlow (positioned) DIV class='positioned indicator'",
+      "position": [665, 50],
+      "bounds": [100, 100],
+      "contentsOpaque": true,
+      "drawsContent": true,
+      "backgroundColor": "#FF0000"
+    },
+    {
       "name": "LayoutBlockFlow (positioned) DIV class='positioned layer'",
       "position": [665, 50],
       "bounds": [100, 100],
       "contentsOpaque": true,
       "drawsContent": true,
       "backgroundColor": "#008000"
     },
     {
       "name": "Frame Horizontal Scrollbar Layer",
       "position": [0, 385],
       "bounds": [385, 15]
     },
     {
       "name": "Frame Vertical Scrollbar Layer",
       "position": [385, 0],
       "bounds": [15, 385]
     },
     {
       "name": "Frame Scroll Corner Layer",
       "position": [385, 385],
       "bounds": [15, 15],
       "drawsContent": true
     }
   ]
 }