Issue 747733  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4ab936cca028e4a4d23924f8bc6f998b11e7909c

commit 4ab936cca028e4a4d23924f8bc6f998b11e7909c
Author: Sandra Sun <sunyunjia@chromium.org>
Date: Wed Aug 09 17:04:16 2017

Reset scroll_sequence_ignored_ at GestureScrollBegin.

Currently in LayerTreeHostImpl, scroll_sequence_ignored_ is only reset to false
at GestureScrollEnd. However, a scroll may end up with GestureFlingStart. In
that case, if the scroll is ignored, the next scroll would also be ignored.

We should reset this value at GestureScrollBegin to make sure each scroll
starts with a clean slate.

Bug:  751773 
Change-Id: Ic2696832ca83628d38283ad957b5686025bf4228
Reviewed-on: https://chromium-review.googlesource.com/601169
Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
Commit-Queue: Sandra Sun <sunyunjia@chromium.org>
Cr-Commit-Position: refs/heads/master@{#493029}
[modify] https://crrev.com/4ab936cca028e4a4d23924f8bc6f998b11e7909c/ui/events/blink/input_handler_proxy.cc

The dupe  http://crbug.com/747733  is a severe bug marked as blocking 61, so requesting merge on this fix.

For the record since we are supposed to say this for merge requests:

Severity: High (drag scrolling stops working permanenently)
Frequency: Affects all Android touch users.  The repro is somewhat specific unclear how common it is in practice, although reported by several Dev/Canary users already

Pls apply appropriate OSs. Thank you.

Mostly Android, but I think it would also affect touch input on Windows and ChromeOS.

This bug requires manual review: M61 has already been promoted to the beta branch, so this requires manual review
Please contact the milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), ketakid@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

+amineer@ for M61 merge review as this bug mostly applicable to Android.

[Bulk Edit]
URGENT - PTAL.
Your bug is labelled as M61 Stable ReleaseBlock, pls make sure to land the fix and get it merged into the release branch ASAP.

Know that this issue shouldn't block the release?  Remove the ReleaseBlock-Stable label.

Thank you.

Approved for M61 branch 3163.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/658af7f5030c5177b5717a4a4d1e2f309e4f96e2

commit 658af7f5030c5177b5717a4a4d1e2f309e4f96e2
Author: Sandra Sun <sunyunjia@chromium.org>
Date: Thu Aug 10 00:10:00 2017

Reset scroll_sequence_ignored_ at GestureScrollBegin.

Currently in LayerTreeHostImpl, scroll_sequence_ignored_ is only reset to false
at GestureScrollEnd. However, a scroll may end up with GestureFlingStart. In
that case, if the scroll is ignored, the next scroll would also be ignored.

We should reset this value at GestureScrollBegin to make sure each scroll
starts with a clean slate.

Bug:  751773 
Change-Id: Ic2696832ca83628d38283ad957b5686025bf4228
Reviewed-on: https://chromium-review.googlesource.com/601169
Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
Commit-Queue: Sandra Sun <sunyunjia@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#493029}(cherry picked from commit 4ab936cca028e4a4d23924f8bc6f998b11e7909c)
Reviewed-on: https://chromium-review.googlesource.com/609478
Reviewed-by: Alexandre Elias <aelias@chromium.org>
Cr-Commit-Position: refs/branch-heads/3163@{#417}
Cr-Branched-From: ff259bab28b35d242e10186cd63af7ed404fae0d-refs/heads/master@{#488528}
[modify] https://crrev.com/658af7f5030c5177b5717a4a4d1e2f309e4f96e2/ui/events/blink/input_handler_proxy.cc

Why do I keep forgetting to update the freaking labels?! >.<

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/069ac8a7c376f5efac270599d771e05036aba356

commit 069ac8a7c376f5efac270599d771e05036aba356
Author: Sandra Sun <sunyunjia@chromium.org>
Date: Mon Aug 14 16:28:27 2017

Tests that GFS can be ignored if the GSB was ignored.

In https://chromium-review.googlesource.com/c/601169, we drop GestureFlingStart
if GestureScrollBegin was ignored. This patch updates the unittest to ensure
the correct behavior.

Bug:  751773 
Change-Id: If641e0e4b60de4dc8cd1218c413d41832f4f7c28
Reviewed-on: https://chromium-review.googlesource.com/609183
Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
Commit-Queue: Sandra Sun <sunyunjia@chromium.org>
Cr-Commit-Position: refs/heads/master@{#494069}
[modify] https://crrev.com/069ac8a7c376f5efac270599d771e05036aba356/ui/events/blink/input_handler_proxy_unittest.cc