GitLab

Since we have decided to instead migrate to Polymer 3:
- Remove the HTML imports polyfill from downloads, extensions, and
Print Preview
- Remove test changes that were made to support the polyfill
- Remove changes to optimize_webui.py that were made to optimize pages
using the polyfill

Bug: 925517, 965770
Change-Id: I531bd3cf7814cb3ca5a32aa80b38f4e1ec16ede6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1873146Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Reviewed-by: Marc-Antoine Ruel <maruel@chromium.org>
Commit-Queue: Rebekah Potter <rbpotter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#708305}