blink: Enable wheel-and-touch-scroll-use-count.html on Linux.

This CL re-enables
virtual/threaded/fast/scroll-behavior/wheel-and-touch-scroll-use-count.html
on Linux since it doesn't seem to be flaking anymore.

Bug: 766357
Change-Id: I58be5caa2263282d167e12a6543520ee05ca9ebe
Reviewed-on: https://chromium-review.googlesource.com/c/1313575
Commit-Queue: Andres Calderon Jaramillo <andrescj@chromium.org>
Reviewed-by: Dmitry Titov <dimich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605534}

third_party/WebKit/LayoutTests/TestExpectations

@@ -5486,7 +5486,7 @@ crbug.com/899222 [ Linux Win ] virtual/user-activation-v2/fast/events/touch/gest
 
 # Sheriff 2018-10-29
 crbug.com/899710 [ Linux Win ] virtual/threaded/http/tests/devtools/tracing/timeline-paint/timeline-paint-with-layout-invalidations.js [ Failure Pass Timeout ]
-crbug.com/766357 [ Linux Mac Win ]  virtual/threaded/fast/scroll-behavior/wheel-and-touch-scroll-use-count.html [ Failure Pass ]
+crbug.com/766357 [ Mac Win ]  virtual/threaded/fast/scroll-behavior/wheel-and-touch-scroll-use-count.html [ Failure Pass ]
 crbug.com/898987 [ Android ] synthetic_gestures/smooth-scroll-tiny-delta.html [ Failure Pass ]
 
 # Sheriff 2018-10-30