Revert of Add a window property to associate RWHVA with its child AX tree ID (patchset #4 id:60001 of https://codereview.chromium.org/2742533003/ )

Reason for revert:
It looks like this causes the (static initializers) sizes step to fail:

https://luci-milo.appspot.com/buildbot/chromium/Linux%20x64/35021

Original issue's description:
> Add a window property to associate RWHVA with its child AX tree ID
>
> Working on making the Chrome OS virtual keyboard accessible to select-to-speak
> and other accessibility services. Currently we link a views::WebView to its
> inner web accessibility tree, but the VK just puts a WebContents directly in
> an aura Window.
>
> This change hooks them up by adding the child AX tree ID as a window property.
>
> BUG=699617
> CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_site_isolation
>
> Review-Url: https://codereview.chromium.org/2742533003
> Cr-Commit-Position: refs/heads/master@{#456445}
> Committed: https://chromium.googlesource.com/chromium/src/+/05107990b575defc12ba29da8ae17a8660a29b67

TBR=sky@chromium.org,dtseng@chromium.org,jam@chromium.org,dmazzoni@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=699617

Review-Url: https://codereview.chromium.org/2751503002
Cr-Commit-Position: refs/heads/master@{#456479}
9 files changed