RFR: 8236912: Preventing NPE when clicking WebView with forward/back mouse buttons

[Robert Lichtenberger]

How strange: Other commits to the master branch of my forked repository
(relating to another issue, already integrated into OpenJFX) are also
showing up here. But the change really only consists of 542ff60e which
contains the fix for JDK-8236912. My older contributions were not checked
into a separate branch (of my fork), maybe that was the problem. If there
is anything else I did wrong, please tell me ;-).

The Changes-Link and the Webrev correctly show that only two files are
changed.

Am Di., 14. Jan. 2020 um 13:02 Uhr schrieb Robert Lichtenberger <
rlichten at openjdk.java.net>:

> As documented in JDK-8236912, WebView did not check whether the idMap
> really contained a mapping for the given button, making it prone to errors,
> when things are extended (as has happened here).
>
> The fix consists of two test cases that show the problem in unfixed
> WebViews and a fix which works analogously to the check whether the given
> event type is mapped.
>
> -------------
>
> Commits:
>  - 542ff60e: Fix null pointer exception when clicking into WebViews with
> forward/back mouse button.
>  - 2109d5a0: Merge remote-tracking branch 'upstream/master'
>  - acfa63be: Merge remote-tracking branch 'upstream/master'
>  - 7c5cf198: 8232524: Test cleanup: terminate background thread upon
> failure.
>  - 7e80839f: 8232524: SynchronizedObservableMap cannot be be protected for
> copying/iterating
>  - 8ecf3545: JDK-8232524 fixed.
>
> Changes: https://git.openjdk.java.net/jfx/pull/85/files
>  Webrev: https://webrevs.openjdk.java.net/jfx/85/webrev.00
>   Issue: https://bugs.openjdk.java.net/browse/JDK-8236912
>   Stats: 18 lines in 2 files changed: 15 ins; 0 del; 3 mod
>   Patch: https://git.openjdk.java.net/jfx/pull/85.diff
>   Fetch: git fetch https://git.openjdk.java.net/jfx pull/85/head:pull/85
>
> PR: https://git.openjdk.java.net/jfx/pull/85
>