Revert "Unify input delay computations for UMA, UKM, and EventTiming"

This reverts commit ae50f0f08fad0ff02cffc9923fed3d4ed6e6d62f.

Reason for revert: Suspect of causing failure of PageLoadMetricsBrowserTest.InputEventsForClick

https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Win%207%20Tests%20x64%20%281%29/49373

Original change's description:
> Unify input delay computations for UMA, UKM, and EventTiming
> 
> This CL moves the input delay computations for UKM to further down the
> pipeline to where they are computed for EventTiming. After this CL, the
> same types of events are logged by both UMA/UKM and EventTiming. The
> WebViewTest is fixed so that the artificial events move further enough
> down the pipeline. The tests checking for pointerCancels are no longer
> applicable since these only applied to the UMA/UKM computations, per
> issue 924278.
> 
> By unifying input delay computation, this CL also fixes frame
> attribution for the UMA/UKM input delays: PageWidgetDelegate does not
> know the target frame (before, it would tell the root that an event has
> occurred even if it occurred in an iframe.
> 
> Bug: 897656, 925130
> Change-Id: I27dba1cbb82ad780d21166a5469001e266612a78
> Reviewed-on: https://chromium-review.googlesource.com/c/1476070
> Reviewed-by: Steven Holte <holte@chromium.org>
> Reviewed-by: Charlie Harrison <csharrison@chromium.org>
> Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
> Commit-Queue: Nicolás Peña Moreno <npm@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#635687}

TBR=tdresser@chromium.org,dtapuska@chromium.org,holte@chromium.org,bmcquade@chromium.org,csharrison@chromium.org,npm@chromium.org

Change-Id: Ibeaa1eb0cd197fee80383a9c7ce5beb63964a713
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 897656, 925130, 936200
Reviewed-on: https://chromium-review.googlesource.com/c/1490401
Reviewed-by: Xiaocheng Hu <xiaochengh@chromium.org>
Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#635752}
18 files changed