html_insert_assets.go: Add comments; readability improvements.
html_insert_assets.go: Add comments; readability improvements.

Bug: skia:10614
Change-Id: I3419201a10c7dfbebd58a52cc15d08ed907994a4
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/482316
Auto-Submit: Leandro Lovisolo <f558143c2568be8d55575d13f30a1fc5cb8009d5@google.com>
Reviewed-by: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>
Commit-Queue: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot