[LayoutNG] Rebaseline selection painting expectations around line height

This patch fixes:
fast/text/selection/selection-with-inline-padding.html
paint/invalidation/selection/selection-rl.html

This patch rebases image failures that NG paints 1px taller than old.
This is by-product but got lgtm at the previous patch:
crrev.com/c/1080442 ([LayoutNG] Fill selection paint line gap.)

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_layout_tests_layout_ng
Bug: 708452
Change-Id: Iba5a07531f2cabf70707e6a9dfaed51fdc653e53
Reviewed-on: https://chromium-review.googlesource.com/1092567Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Commit-Queue: Yoichi Osato <yoichio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565924}

third_party/WebKit/LayoutTests/flag-specific/enable-blink-features=LayoutNG/paint/invalidation/selection/selection-rl-expected.txt

+{
+  "layers": [
+    {
+      "name": "LayoutView #document",
+      "bounds": [800, 600],
+      "drawsContent": false,
+      "backgroundColor": "#FFFFFF"
+    },
+    {
+      "name": "Scrolling Layer",
+      "bounds": [800, 600],
+      "drawsContent": false
+    },
+    {
+      "name": "Scrolling Contents Layer",
+      "bounds": [800, 600],
+      "contentsOpaque": true,
+      "backgroundColor": "#FFFFFF",
+      "paintInvalidations": [
+        {
+          "object": "NGPaintFragment",
+          "rect": [772, 8, 20, 143],
+          "reason": "selection"
+        }
+      ]
+    }
+  ],
+  "objectPaintInvalidations": [
+    {
+      "object": "NGPaintFragment",
+      "reason": "selection"
+    }
+  ]
+}
+