RFR: 8260257: [Linux] WebView no longer reacts to some mouse events [v2]

[Arun Joseph]

> Timer in RunLoopGeneric has an open bug in WebKit (https://bugs.webkit.org/show_bug.cgi?id=189335) causing the timer to remain active even after firing.
> 
> Reverting back to WebCore Timer for ScrollAnimation in Linux.

Arun Joseph has updated the pull request incrementally with one additional commit since the last revision:

  Add system test

-------------

Changes:
  - all: https://git.openjdk.java.net/jfx/pull/404/files
  - new: https://git.openjdk.java.net/jfx/pull/404/files/480c0d98..903093ac

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jfx&pr=404&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jfx&pr=404&range=00-01

  Stats: 161 lines in 3 files changed: 160 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jfx/pull/404.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/404/head:pull/404

PR: https://git.openjdk.java.net/jfx/pull/404