Make contenteditable="false" element as atomic node for selection motion

LayoutTests/editing/selection/move-by-line-004-expected.txt

Index: LayoutTests/editing/selection/move-by-line-004-expected.txt
diff --git a/LayoutTests/editing/selection/move-by-line-004-expected.txt b/LayoutTests/editing/selection/move-by-line-004-expected.txt
index 4909e1726c765f0e931140f52b3fbf1ff694d9e4..47ac0aa5224d311491a674f0471b2dd60b4af450 100644
--- a/LayoutTests/editing/selection/move-by-line-004-expected.txt
+++ b/LayoutTests/editing/selection/move-by-line-004-expected.txt
@@ -1,6 +1,15 @@
-Test that moving the caret with line granularity within the highest editable root works across non-editable content.
+Test that moving the caret with line granularity within the highest editable root doesn't work across non-editable content.
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+Move forward line x 1
+PASS selection.anchorNode == '[object Text]' is true
+PASS selection.anchorOffset is 9
+Move backward line x 1
+PASS selection.anchorNode == '[object Text]' is true
+PASS selection.anchorOffset is 0
+PASS successfullyParsed is true
+
+TEST COMPLETE
 
-PASS
-apple pie
-pineapple
-apple juice