GitLab

For our unittests Polymer wasn't working, this CL changes it by:
1. Always adding the HTML import polyfil.
2. Always importing the the Polymer config at the top, so any test using
Polymer elements work.
3. If there is any dependency in the Files app Polymer elements (files
inside //ui/file_manager/file_manager/foreground/elements/) it uses the
elements_bundle.html instead of individual JS files.

When I activated Polymer and imported the elements_bundle.html some
tests started failing because they require the chrome.fileManagerPrivate
mock.

FileTransferController test uses ListContainer that requires the
<files-spinner>.  Also add the closing tag </cr-input> so the adjacent
<input> remains outside the <cr-input> allowing the focus to flow
properly as the test setting the focus on #test-input started failing
once <cr-input> Polymer became fully functional.

NOTE: This fix is only relevant for non-JS module unittest, we're
migrating unittest to JS module and this problem doesn't happen when
using the built-in JS import.

Bug: 1102263
Change-Id: I2ea80bbe93afca2521bfa5ab9fcd6c32fcf8ecc0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2573696
Commit-Queue: Noel Gordon <noel@chromium.org>
Commit-Queue: Luciano Pacheco <lucmult@chromium.org>
Auto-Submit: Luciano Pacheco <lucmult@chromium.org>
Reviewed-by: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#833573}