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

third_party/WebKit/LayoutTests/platform/linux/paint/invalidation/svg/tspan-dynamic-positioning-expected.txt

 {
   "layers": [
     {
       "name": "LayoutView #document",
       "bounds": [800, 600],
       "contentsOpaque": true,
       "drawsContent": true,
       "paintInvalidations": [
         {
-          "object": "LayoutSVGInlineText #text",
-          "rect": [200, 185, 240, 19],
-          "reason": "forced by layout"
-        },
-        {
-          "object": "LayoutSVGTSpan tspan id='ts'",
-          "rect": [200, 185, 240, 19],
-          "reason": "full"
-        },
-        {
           "object": "LayoutSVGText text",
           "rect": [200, 185, 240, 19],
           "reason": "forced by layout"
         },
         {
           "object": "LayoutSVGInlineText #text",
           "rect": [20, 5, 240, 19],
           "reason": "forced by layout"
         },
         {
@@ skipping 30 matching lines @@
       "object": "LayoutSVGInlineText #text",
       "reason": "forced by layout"
     },
     {
       "object": "InlineTextBox 'This text should be at visible at 200,200'",
       "reason": "forced by layout"
     }
   ]
 }