Revert "[Profiles] Use new colored default avatars for taskbar badges"

This reverts commit 6b7290b3.

Reason for revert: memory regression on Mac (crbug.com/1146299)

Original change's description:
> [Profiles] Use new colored default avatars for taskbar badges
>
> Recently, all logic around profile avatars has been integrated into
> ProfileAttributesEntry::GetAvatarIcon() incl. new features such as
> colored default avatars.
>
> This CL updates code that generates taskbar badges on Windows to
> delegate most of its logic to GetAvatarIcon(). Only the pieces needed
> for obtaining ImageLoadStatus remained in this code.
>
> The only behavioral change is for non-GAIA avatars: high-res /
> 2x windows old avatars are returned instead of low-res avatars. This
> means more downscaling is needed than before. This will be addressed
> by further CLs that will make GetAvatarIcon() respect preferred_size in
> more cases.
>
> Bug: 1122559
> Change-Id: I5eecc7c6647dc78f9ff92d74edb64214a48e8e63
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2514153


> Commit-Queue: Jan Krcal <jkrcal@chromium.org>
> Reviewed-by: David Roger <droger@chromium.org>
> Auto-Submit: Jan Krcal <jkrcal@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#824494}

TBR=droger@chromium.org,jkrcal@chromium.org

Change-Id: I66f7b806a25b910d35b55f02805c4c8216049f55
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1122559, 1146299
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2521118


Reviewed-by: Jan Krcal <jkrcal@chromium.org>
Commit-Queue: Jan Krcal <jkrcal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#824833}