Update to GTK WebKit 2.28.4 https://webkitgtk.org/2020/07/28/webkitgtk2.28.4-released.html
------------- Commit messages: - 8252381: Cherry pick GTK WebKit 2.28.4 changes Changes: https://git.openjdk.java.net/jfx/pull/289/files Webrev: https://webrevs.openjdk.java.net/jfx/289/webrev.00 Issue: https://bugs.openjdk.java.net/browse/JDK-8252381 Stats: 174 lines in 21 files changed: 123 ins; 16 del; 35 mod Patch: https://git.openjdk.java.net/jfx/pull/289.diff Fetch: git fetch https://git.openjdk.java.net/jfx pull/289/head:pull/289 PR: https://git.openjdk.java.net/jfx/pull/289
