Remove unused method define() in the private mojoPrivate extensions API.

Bug: 699569,718047
Change-Id: I2ebda3e66b6cb7f74cb6bc3f577f978022374a14
Reviewed-on: https://chromium-review.googlesource.com/750191
Reviewed-by: Ken Rockot <rockot@chromium.org>
Commit-Queue: Yuzhu Shen <yzshen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#513529}
5 files changed