webkit_tests failing on chromium.webkit/WebKit Win7 (dbg)

Builders failed on: 
- WebKit Win7 (dbg): 
  https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Win7%20%28dbg%29


One tests fails repeatedly and unexpectedly:
fast/events/pointerevents/pointer-event-consumed-touchstart-in-slop-region.html

More often than not, the message is:
This is a testharness.js-based test.
FAIL Tests that the TouchMoves are not suppressed if the touch start is consumed. assert_equals: expected 3 but got 2
Harness: the test ran to completion.


Assigning the bug to component Blink>Input as the reason for this
failure is still not clear.
Previous revert attempts were unsuccessful (CL 2832503005)

Regression ranges: (chromium: 465743 - 465806)
384441de (yzshen): Network service: handle the failure case of frame requests.
6527e1ef (danakj): Remove PaintCanvas::writePixels
431d5028 (joedow): Re-enabling breakpad support for Windows
b55e4c29 (khorimoto): Disable logging in CryptAuthBluetoothLowEnergyWeaveClientConnectionTest. It was too spammy.
0b8df9f9 (rjkroege): Re-order fields for better alignment
444e30cb (minch): Open system menu when click the status tray with volume popup opened.
25e4011a (dpapad): WebUI: Fix calculation of md-select text and arrow spacing.
b985210b (kouhei): [ES6 modules] Integrate ModuleTreeLinkerRegistry into ModulatorImpl back-plane
d8136253 (slan): Add substitute_tmpl.grd to translation_expectations.pyl.
0e518b61 (jamescook): cros: Move IsUserSupervised and IsUserChild off SystemTrayDelegate
a022d09f (xingliu): Add fieldtrial_testing_config for parallel downloading.
b8a8a089 (benwells): Don't show the Location Settings Dialog if the tab isn't interactable.
f628d6b4 (eroman): [refactor] Extract the platform-specific TrustStore instantiations and
bca0b3fb (afakhry): Remove unused virtual display code
da81aa1d (glebl): Add wpt/css/CSS2/positioning LayoutNG virtual test suite.
0462cff6 (lpy): Node.prototype.baseURI should not be nullable
74a524ac (Tommy Nyquist): Add support for parsing Chrome Variations field trial config.
78d34174 (Adrienne Walker): Remove unused direct raster GraphicsContextCanvas mode
ec95c1aa (megjablon): Add snackbar param for the Data Saver Promo field trial to the testing config
ed24fe20 (binji): [SharedArrayBuffer] Add "AllowShared" extended attribute, used for WebGL
416a5cb2 (baxley): Fix variable name in test helper looking for error page.
5f7f5b03 (sadrul): mus: Run the gpu unittests on chromeos bots.
6db4113f (brucedawson): Copy dbghelp.dll to output directory
211430bf (dougarnett): Return chrome-proxy-ect header code (post M59 branch)
adebcac2 (pilgrim): Replace DCHECK with DCHECK_EQ and DCHECK_GT as appropriate in modules/accessibility
defa0b4d (sgurun): Update reference to GetChromiumSrcDir()
e4223807 (davidben): Remove SSLPrivateKey metadata hooks.
ae7d1d17 (pavely): [Sync] Small vector optimization
b8cba92b (qyearsley): Reland of "In run-webkit-tests, start xvfb if necessary".
b67d2626 (twellington): [Home] Don't hide keyboard while arrowing through find in page results
b4c2c712 (eugenebut): Removed dialog_overrides.js script.
54ba8b46 (tommycli): Views UI: Improve middle-click pasting onto selected text behavior.
0bcba700 (ajuma): cc: Remove unused typedefs in layer_impl.h
4179f08f (warx): cros: close dialog when shill detects captive portal network switched to online
f7fcc45c (shess): [sql] Verify control of close-time WAL checkpoint.
08590c23 (rsorokin): Chromad: Fix deleting user data
11395368 (reed): SkBitmap and SkPixelRef no longer need lock/unlock
d920c93c (Sunny Sachanandani): cc: Make scheduler run incoming frame after previous deadline.
688b9d10 (Stephen Martinis): //tools/perf: Remove old legacy sharding
8761c218 (kylechar): Fix SurfaceIds in mus with surface sync off.
2edbc3bc (tzik): Rewrite base::Bind to base::BindOnce with base_bind_rewriters in //chrome/browser/media_galleries
fc500b52 (rsleevi): Reduce the set of WoSign/StartCom domains to the Alexa Top 100K
cd4b25ed (rdsmith): Add OWNERS file for content/network.
ab6b83a2 (ftirelo): Sends execution mode to the Software Reporter.
4d3a1c9c (sergeyu): Filter X session output in linux_me2me_host.py.
d07818d9 (dschuyler): [MD settings] avoid dialog resizing in add exception
9cf9295d (davidben): Use PKCS7_get_raw_certificates in x509_certificate_bytes.cc.
b59a494f (glebl): Add external/wpt/css/CSS2/abspos LayoutNG virtual test suite.
ddb3babc (phosek): Use $root:default as a "default" rule
8aeea939 (rogerm): Revert of Plumb activation time to main (patchset #16 id:280001 of https://codereview.chromium.org/2778223005/ )
3c1e950b (aleventhal): Test for anything falsey as a fail value for element.accessibleNode. Test for anything truthy as a fail value on a static text node's accessibleNode.
d022298a (tdresser): Remove input-dev@ as histogram owner.
7b8ed8a2 (pdr): Refactor LayerTreeImpl's scrollbar map to be keyed on element ids
9cddc0b9 (dalecurtis): Convert MediaLog from being ref counted to owned by WebMediaPlayer.
847504d1 (elawrence): Deprecate Once-Per-Origin Navigation histograms
fed3fc66 (rouslan): Log duplicate shipping option ID warning in web payments API.
e7c580f5 (pkotwicz): Fix test slowness introduced by https://codereview.chromium.org/2771793003
e8e89d55 (khorimoto): [CrOS Tether] Add tether network properties (battery percentage, carrier, and signal strength) to the Chrome OS networking stack.
a4be5c70 (rogerm): Reland of Disable flaky WebNavigationApiTest.CrossProcessHistory. (patchset #1 id:1 of https://codereview.chromium.org/2830813002/ )
38718938 (aleventhal): When an ARIA grid or treegrid is used, pass that role through while still supporting the table interface. Essentially, the grid/treegrid roles can be understood as a subclass of a table role. Also do some cleanup for table/grid/treegrid handling.
7b4caa42 (wkorman): Paint text underline/overline decorations before painting text.
c751fcc6 (pkotwicz): [WebAPKs] Fix WebAPK updates when Web Manifest does not specify color
c817f241 (davidben): Roll src/third_party/boringssl/src bc6a76b0e..777fdd644
ce0b29ba (twellington): Launch "Update Chrome" menu item