Reland: New object attributes to disambiguate description sources

Original: CL:2799998

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.

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

Bug: 1194991
Change-Id: I6f0a3a49a0baa181ea39151f8591a13725e089f3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2826470
Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
Auto-Submit: Aaron Leventhal <aleventhal@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: Alex Gough <ajgo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#872910}
GitOrigin-RevId: a9456c81c3b65a0758a7ef1022325138b6e96aa2
1 file changed