Update parser to support <t>, <template>, /> syntax

Specs: Update parser to support <t>, <template>, "/>" syntax
Specs: Fix scripts to run at </script> not <script>
Specs: Update parsing to delay on pending imports before running
scripts or firing 'load'
Specs: Fire 'load' at Application or Module rather than Document
Specs: Imply there's going to be a start tag token observer callback
so that you can implement prefetching for custom elements

R=abarth@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/ea948631759be8ac46b0846d1488ba915e3b6111

[abarth-chromium, 2014-10-24 18:42:24]

abarth@chromium.org changed reviewers:
+ abarth@chromium.org

[abarth-chromium, 2014-10-24 18:42:24]

lgtm

[ojan, 2014-10-24 19:23:50]

ojan@chromium.org changed reviewers:
+ ojan@chromium.org

[ojan, 2014-10-24 19:23:51]

Nit: please have the change description make it clear that this is a spec
change.

[Hixie, 2014-10-24 20:28:04]

Committed patchset #2 (id:20001) manually as
ea948631759be8ac46b0846d1488ba915e3b6111 (presubmit successful).