GitLab

The |flattenhtml| parameter, which the code previously relied to
inline several icons, is not supported (purposefully) by
generate_grd(). Addressed as follows:

 - icon_tabs.svg: Served from chrome://omnibox/, only used there.
 - cancel_red.svg and check_circle_green.svg: Exposed via
   chrome://resources/ URLs
 - ic_download.svg: Inlined in CSS directly, since this WebUI
   doesn't use <iron-icon>

Bug: 1132403
Change-Id: Ib1738228cc90b193b8534ca9b27d1fb571503f72
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2536152Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Reviewed-by: manuk hovanesian <manukh@chromium.org>
Commit-Queue: dpapad <dpapad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#827954}