Convert editing/inserting/insert-div-018.html to use w3c test harness
This patch converts "editing/inserting/insert-div-018.html" to use w3c test
harness to avoid pixel comparison since this test doesn't need to check
pixels for simplify test case.
crrev.com/2124213002 Make EphemeralRange constructor not to accept invalid start
and end positions.
BUG=n/a
TEST=n/a; no behavior changes
Committed:
https://crrev.com/cf232d40c5eba8f30c069b6774c3c68d4caa2b0c
Cr-Commit-Position: refs/heads/master@{#404103}