Observed that the window manager takes care of showing and hiding children because we set `gtk_window_set_transient_for`.
Works since Ubuntu 16.04. This PR removes the code to show or hide children because it "duplicates" the operation and might lead to unknown bugs. ------------- Commit messages: - Remove show or hide children Changes: https://git.openjdk.org/jfx/pull/1279/files Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1279&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8319341 Stats: 31 lines in 4 files changed: 0 ins; 31 del; 0 mod Patch: https://git.openjdk.org/jfx/pull/1279.diff Fetch: git fetch https://git.openjdk.org/jfx.git pull/1279/head:pull/1279 PR: https://git.openjdk.org/jfx/pull/1279
