Clean backport to jfx11u. Tested on all three platforms, along with my other in-progress backports, all of which are aggregated in my [`kevinrushforth:test-kcr-11.0.12`](https://github.com/kevinrushforth/jfx11u/commits/test-kcr-11.0.12) branch.
------------- Commit messages: - 8264990: WebEngine crashes with segfault when not loaded through system classloader Changes: https://git.openjdk.java.net/jfx11u/pull/11/files Webrev: https://webrevs.openjdk.java.net/?repo=jfx11u&pr=11&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8264990 Stats: 342 lines in 7 files changed: 315 ins; 7 del; 20 mod Patch: https://git.openjdk.java.net/jfx11u/pull/11.diff Fetch: git fetch https://git.openjdk.java.net/jfx11u pull/11/head:pull/11 PR: https://git.openjdk.java.net/jfx11u/pull/11
