Convert editing/inserting/insert-div-009.html to use w3c test harness
This patch converts "editing/inserting/insert-div-009.html" to use w3c test
harness to simplify test script for improving code health.
BUG=n/a
TEST=n/a; no behavior changes
Committed:
https://crrev.com/e4bb1b4bca6ca41c71fbe2787d78e86f9d0a4899
Cr-Commit-Position: refs/heads/master@{#418763}