Don't invalidate rect if it's covered by fully invalidated parent's visual rect

third_party/WebKit/LayoutTests/platform/linux/paint/invalidation/invalidation-after-opacity-change-subtree-expected.txt

 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [785, 2350],
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
         {
           "object": "LayoutBlockFlow (positioned) DIV id='absolute'",
           "rect": [8, 2000, 777, 350],
           "reason": "subtree"
         },
         {
           "object": "LayoutBlockFlow (positioned) DIV id='absolute'",
           "rect": [8, 2000, 777, 350],
           "reason": "subtree"
         },
         {
           "object": "LayoutBlockFlow P",
           "rect": [8, 2200, 777, 100],
           "reason": "subtree"
         },
         {
           "object": "LayoutBlockFlow P",
-          "rect": [8, 2200, 777, 100],
-          "reason": "subtree"
-        },
-        {
-          "object": "LayoutBlockFlow P",
           "rect": [8, 2050, 777, 100],
           "reason": "subtree"
         },
-        {
-          "object": "LayoutBlockFlow P",
-          "rect": [8, 2050, 777, 100],
-          "reason": "subtree"
-        },
         {
           "object": "LayoutText #text",
           "rect": [8, 2046, 767, 107],
           "reason": "subtree"
         },
         {
           "object": "LayoutText #text",
           "rect": [8, 2046, 767, 107],
           "reason": "subtree"
         },
@@ skipping 103 matching lines @@
       "object": "InlineTextBox 'This text should be visible in the'",
       "reason": "subtree"
     },
     {
       "object": "InlineTextBox 'output.'",
       "reason": "subtree"
     }
   ]
 }