Allow recursive NameFromContents of Role::kStrong and Role::kEmphasis

Roles that allow NameFrom::kContents were not adding the text of
descendants with Role::kStrong or Role::kEmphasis.

This could cause screen readers read a portion of a word in some cases.

Bug: 1047549
Change-Id: Iaacd8e485684b61ee0977c44d31479f6aa3d108a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2032514
Commit-Queue: Aaron Leventhal <aleventhal@chromium.org>
Reviewed-by: Kurt Catti-Schmidt <kschmi@microsoft.com>
Reviewed-by: Aaron Leventhal <aleventhal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#737775}
7 files changed