Turn on CompositeOpaqueFixedPosition for test and rebase tests.

third_party/WebKit/LayoutTests/compositing/layer-creation/fixed-position-under-transform-expected.txt

 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [785, 5021],
       "contentsOpaque": true,
       "drawsContent": true
     },
     {
       "name": "LayoutBlockFlow DIV id='transform'",
       "position": [108, 113],
       "transformOrigin": [284.5, -100],
       "bounds": [256, 256],
+      "contentsOpaque": true,
       "drawsContent": true,
       "transform": [
         [1, 0, 0, 0],
         [0, 1, 0, 0],
         [0, 0, 1, 0],
         [0, 1000, 0, 1]
       ]
     },
     {
       "name": "LayoutBlockFlow (positioned) DIV id='overlap'",
       "position": [0, 1000],
       "bounds": [500, 500],
       "contentsOpaque": true,
       "drawsContent": true,
       "backgroundColor": "#008000"
     }
   ]
 }