The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/621e5c1c2e0a840308a15e58272228537fe482ab

commit 621e5c1c2e0a840308a15e58272228537fe482ab
Author: Findit <findit-for-me@appspot.gserviceaccount.com>
Date: Sat Oct 13 03:54:15 2018

Revert "Reland "Fling bubbles from OOPIF properly.""

This reverts commit 21ba6121d2ba5821515bcb9f3fdf768204425061.

Reason for revert:

Findit (https://goo.gl/kROfz5) identified CL at revision 599360 as the
culprit for flakes in the build cycles as shown on:
https://findit-for-me.appspot.com/waterfall/flake/flake-culprit?key=ag9zfmZpbmRpdC1mb3ItbWVyQwsSDEZsYWtlQ3VscHJpdCIxY2hyb21pdW0vMjFiYTYxMjFkMmJhNTgyMTUxNWJjYjlmM2ZkZjc2ODIwNDQyNTA2MQw

Sample Failed Build: https://ci.chromium.org/buildbot/chromium.chromiumos/linux-chromeos-rel/14616

Sample Failed Step: viz_content_browsertests

Sample Flaky Test: BrowserSideFlingBrowserTest.GFCGetsBubbledFromOOPIF

Original change's description:
> Reland "Fling bubbles from OOPIF properly."
> 
> This is a reland of a12ef847a57f4aa0282ca47b555c04da18b00f9e
> 
> The reland has the following two fixes:
> 1- In the added tests, we wait for the ack of the GSB from the parent view to make
> sure that GFS is processed after GSB has been bubbled to avoid the flakiness.
> 2- Early return in BubbleScrollEvent to avoid crbug.com/828422
> 
> Original change's description:
> > Fling bubbles from OOPIF properly.
> >
> > While we are bubbling a scroll sequence GFS is sent to the fling controllers
> > of both the oopif and the bubbling target. The fling controller of the oopif
> > calls progressFling and generates a GSU with inertial phase, the GSU gets acked
> > immediately before getting sent to the renderer since we are in bubbling mode.
> > Then the oopif's fling controller receives the unconsumed GSU ack and generates
> > a GSE to complete the scrolling sequence on the oopif. The bubbling target's
> > fling controller receives and processes the GFS and generates GSUs which are
> > sent to the target's renderer.
> >
> > If the GSE generated by the oopif's fling controller gets bubbled before
> > the GFS, the bubbling target gets reset and the target does not receive the
> > GFS. This cl fixes the issue by making sure that the events generated by the
> > oopif's fling controller are not bubbled to the target. Also in case of
> > GFS bubbling, the GFC should also get sent to the bubbling target to make
> > sure that the fling controller in charge of flinging receives the GFC.
> >
> >
> > Bug:  884728 ,  249063 
> > Test: BrowserSideFlingBrowserTest.[Touchpad|Touchscreen]FlingBubblesFromOOPIF
> > Change-Id: I064944f125bebcb746f329af4cfb117f3be94ff0
> > Reviewed-on: https://chromium-review.googlesource.com/c/1274193
> > Reviewed-by: Kevin McNee <mcnee@chromium.org>
> > Reviewed-by: Charlie Reis <creis@chromium.org>
> > Commit-Queue: Charlie Reis <creis@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#599001}
> 
> Bug:  884728 ,  249063 
> Change-Id: I1528d904e84ff85f7828392c2b0178a42869d529
> Reviewed-on: https://chromium-review.googlesource.com/c/1278963
> Reviewed-by: Kevin McNee <mcnee@chromium.org>
> Reviewed-by: Charlie Reis <creis@chromium.org>
> Commit-Queue: Sahel Sharify <sahel@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#599360}

Change-Id: I5553104cdf30a18fb9399b486d5c403a67dda409
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug:  884728 ,  249063 ,  895059 
Reviewed-on: https://chromium-review.googlesource.com/c/1279943
Cr-Commit-Position: refs/heads/master@{#599483}
[modify] https://crrev.com/621e5c1c2e0a840308a15e58272228537fe482ab/content/browser/frame_host/cross_process_frame_connector.cc
[modify] https://crrev.com/621e5c1c2e0a840308a15e58272228537fe482ab/content/browser/renderer_host/input/fling_browsertest.cc
[modify] https://crrev.com/621e5c1c2e0a840308a15e58272228537fe482ab/content/browser/renderer_host/render_widget_host_input_event_router.cc
[modify] https://crrev.com/621e5c1c2e0a840308a15e58272228537fe482ab/content/browser/renderer_host/render_widget_host_input_event_router.h
[modify] https://crrev.com/621e5c1c2e0a840308a15e58272228537fe482ab/content/browser/renderer_host/render_widget_host_view_child_frame.cc

sahel@ - please take a look :-)