libdot: closure: update to v20190929
libdot: closure: update to v20190929

Newer versions break even more, so update to this version to help
shake out a few changes first.

Change-Id: I666496d9220e9a2bb4eb2e3d754309ed2021c42e
Reviewed-on: https://chromium-review.googlesource.com/c/apps/libapps/+/2151862
Reviewed-by: Joel Hockey <9ecfc52dc2ffef73afac73f3495f294aeddf1231@chromium.org>
Tested-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>

chromium/hterm,chromium/hterm,chromium/hterm,chromium/hterm