hterm: hterm_test.html: Remove non-existent test. Add missing test.
hterm: hterm_test.html: Remove non-existent test. Add missing test.

* Comment hterm_keyboard_bindings_tests.js: it does not exist (yet?)
* Add hterm_pubsub_tests.js: Was not referenced.
* Sort mostly alphabetically to easily compare to ls *_tests.js. I left
  vt_canned_tests last since it has output someone might want to look at.

Change-Id: I88c472965a119e34e92075c6750aeda6ba7b7f40
Reviewed-on: https://chromium-review.googlesource.com/417900
Tested-by: Evan Jones <ee9800e8361e948d0106b38fc6e6311ee238beed@evanjones.ca>
Reviewed-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>

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