Revert "Move RequestDecode and RequestPresentationCallback from WebLayerTreeView (8/n)"

This reverts commit 07221eb8f25da04080febdc4f18e306eb6d612a5.

Reason for revert: Findit suspects this CL at https://crbug.com/947833. Let me revert this to check if it helps the layout test.

Original change's description:
> Move RequestDecode and RequestPresentationCallback from WebLayerTreeView (8/n)
>
> The RequestDecode() method moves to WebWidgetClient, and is implemented
> in RenderWidget.
>
> The RequestPresentationCallback() is removed, and a method is added as
> WebWidgetTestProxy::RequestCompositeAndPresentation() for test_runner to use
> instead. It acts like RequestPresentation() but forces the scheduled sync
> composite to run the full compositor stack instead of just the main frame
> animation step.
>
> This removes the LayerTreeView::SynchronouslyComposite() method and
> changes callers to it to call WebWidgetTestProxy::ScheduleAnimation()
> instead of duplicating that logic out in production code.
>
> This moves ~60 lines of production code into content/shell/test_runner/
> to remove them from chrome.exe, as well as straight up removing another
> ~80 lines of production code. Now RenderWidget and LayerTreeView
> have no concept of synchronous composites, as they are entirely
> managed by WebWidgetTestProxy.
>
> We now have only one caller of LayerTreeHost::Composite() in web tests
> instead of previously having 4.
>
> R=​dcheng@chromium.org
>
> Bug: 912193
> Change-Id: I26cd9cbbe503e9b876a146f2eebccbf8e9121190
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1544820
> Commit-Queue: Philip Rogers <pdr@chromium.org>
> Reviewed-by: Philip Rogers <pdr@chromium.org>
> Reviewed-by: Avi Drissman <avi@chromium.org>
> Auto-Submit: danakj <danakj@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#645998}

TBR=avi@chromium.org,danakj@chromium.org,dcheng@chromium.org,pdr@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 912193, 947833
Change-Id: Id8ee3889e355e15feb0d7ae3d1eeae0ef848c4be
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1546800
Commit-Queue: Makoto Shimazu <shimazu@chromium.org>
Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#646188}
18 files changed