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The cl does 4 things:
(1) Adds a list (in gyp) for the feedback_consent js files.
(2) Uses build-html.py to build feedback_consent.html from a template.
(3) Adds an action to run jscompile over the feedback_consent js files.
(4) Fixes the errors/warnings reported by jscompile.

BUG=

Review URL: https://codereview.chromium.org/964403004

Cr-Commit-Position: refs/heads/master@{#318822}