GitLab

Add a method to query the focus state of the PDF plugin. This
information will be used to implement focus changes in the
PdfAccessibilityTree.

This CL is partially based on code borrowed from
https://crrev.com/c/2230804/21.

Bug: 1015350
Change-Id: I3475010b8aec146f258d5f481ec2d60133d1acda
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2351721
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Ankit Kumar 🌪️ <ankk@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#798789}