[Sheriff] Revert "New object attributes to disambiguate description sources"

This reverts commit 80e97242.

Reason for revert: Suspected to cause a11y tree failures, https://ci.chromium.org/ui/p/chromium/builders/ci/Win7%20Tests%20(1)/116006/overview

Original change's description:
> New object attributes to disambiguate description sources
>
> NVDA screen reader team has asked for some changes to how descriptions
> are exposed in IAccessible2 so that they don't have to automatically
> announce tooltips, while still announcing other annotations.
>
> New object attributes:
> * "description" now reflects aria-description, but not other description
>   sources. This matches what Firefox does now.
> * "description-from" has one one the following values:
>   - "aria-description"
>   - "aria-describedby"
>   - "ruby-annotation"
>   - "summary"
>   - "table-caption"
>   - "tooltip" (either via @title or aria-describedby + role="tooltip")
>   - "button-label" (when the name was from something else)
>
> The above may require future tweaks but has been agreed to in principle
> with NVDA and Mozilla.
>
> Bug: 1194991
> Change-Id: Ie20486e569b6f892e85c143119d1eea4d91efaf7
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2799998


> Commit-Queue: Aaron Leventhal <aleventhal@chromium.org>
> Auto-Submit: Aaron Leventhal <aleventhal@chromium.org>
> Reviewed-by: Will Harris <wfh@chromium.org>
> Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#871966}

Bug: 1194991
Change-Id: I34b222fe6ebcebbf788b8e1825f8920d2d8b00d0
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2825893
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Anatoliy Potapchuk <apotapchuk@google.com>
Auto-Submit: Anatoliy Potapchuk <apotapchuk@google.com>
Cr-Commit-Position: refs/heads/master@{#872385}