Revert "[a11y] Avoid clearing/resetting focus on an already focus event"

This reverts commit 22871e619f2480674dc6edc530cda57afe88ae9b.

Reason for revert: Prevents keyboard from opening on Android in 
                   some cases. See: b/332846880 and b/338514115.

Bug: 332846880, 338514115

Original change's description:
> [a11y] Avoid clearing/resetting focus on an already focus event
>
> When we set the focus via an accessibility API on an element that
> is already focused, we first remove the focus and reset it. This
> leads to blur/focusout/focusin events being fired again.
>
> This behavior is different than the one we get when we set focus
> programmatically, with a mouse, or a keyboard, on an already
> focused element. In order to keep the same experience across all
> input modalities, this CL removes the divergent focus behavior
> for accessibility APIs.
>
> We tried to remove this code two years ago (CL:3547796) but it
> got reverted due to bug:40850837. This time, I made sure to discuss
> this issue with the Chrome Android accessibility owners to make 
> sure it's safe to remove. They landed CL:5345750, and then gave
> us the green light to land this CL.
>
> Fixed: 40830307
> Change-Id: I8ad70ed6813e0ae52238292f1b7e6d038a5238f1
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5356613
> Reviewed-by: Mark Schillaci <mschillaci@google.com>
> Commit-Queue: Benjamin Beaudry <benjamin.beaudry@microsoft.com>
> Auto-Submit: Benjamin Beaudry <benjamin.beaudry@microsoft.com>
> Cr-Commit-Position: refs/heads/main@{#1270380}

Change-Id: I0e6477b33d715387a0dd7104182a53cb346ae4f6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5531959
Commit-Queue: Mark Schillaci <mschillaci@google.com>
Commit-Queue: Benjamin Beaudry <benjamin.beaudry@microsoft.com>
Reviewed-by: Benjamin Beaudry <benjamin.beaudry@microsoft.com>
Auto-Submit: Mark Schillaci <mschillaci@google.com>
Cr-Commit-Position: refs/heads/main@{#1299388}