Convert editing/inserting/typing-00[1-3].html to use w3c test harness

This patch converts "editing/inserting/typing-00[1-3].html" to use w3c
test harness and consolidates into "typing.html" to simplify test case
for ease of maintenance.

This patch is a preparation of getting rid of grammar checking feature.

BUG=619452
TEST=n/a; this patch changes a test file

Review-Url: https://codereview.chromium.org/2184503003
Cr-Commit-Position: refs/heads/master@{#407732}
22 files changed