Revert of Reland #4: Ensure WebView notifies desktop automation on creation, (patchs...

Revert of Reland #4: Ensure WebView notifies desktop automation on creation,  (patchset #1 id:1 of https://codereview.chromium.org/940763002/)

Reason for revert:
Still flakes on bots.

Original issue's description:
> Reland #4: Ensure WebView notifies desktop automation on creation, destruction, and change
>
> Previous attempts:
> https://codereview.chromium.org/880063002
> https://codereview.chromium.org/895623003/
> https://codereview.chromium.org/890013006/
> https://codereview.chromium.org/907973004/
>
> This latest attempt removes the logic that reloads ChromeVox at the beginning of a test.
>
> Locally, under extremely heavy load, tests progressively ran slowe. The same copy of a test ran 1 second slower than a previous copy. Ultimately, this led to a timeout.
>
> With the above change, this no longer occurs and hopefully fixes the flakeyness.
>
> Change is located in chromevox_e2e_test_base.js.
>
> TBR=dmazzoni@chromium.org
>
> Committed: https://crrev.com/47cb3b3798d325f3083565a05a2dcdaee117c296
> Cr-Commit-Position: refs/heads/master@{#316950}

TBR=dmazzoni@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/939853003

Cr-Commit-Position: refs/heads/master@{#316971}