When converter was changed, `setText` method of spinner was not invoked to update the spinner text using new converter.
Added a listener to converter property of `SpinnerValueFactory` to call `setText` so that spinner text is updated using new converter. Added unit test to validate the fix. Along with spinner of Double type, added a spinner of Integer type as well so that the fix is validated using 2 types of spinner. ------------- Commit messages: - Fix spinner converter issue Changes: https://git.openjdk.org/jfx/pull/1057/files Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1057&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8154038 Stats: 58 lines in 2 files changed: 58 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jfx/pull/1057.diff Fetch: git fetch https://git.openjdk.org/jfx pull/1057/head:pull/1057 PR: https://git.openjdk.org/jfx/pull/1057
