[PATCH] 8161282: FXCanvas does not forward horizontal mouse scroll events to the embedded scene

[Alexander Nyssen]

Hi Kevin,

attached please find an initial patch for https://bugs.openjdk.java.net/browse/JDK-8161282 <https://bugs.openjdk.java.net/browse/JDK-8161282>.

The patch is not as minimal as I had hoped, as the EmbeddedSceneInterface had to be changed to differentiate between mouse and scroll events (while up to now, scroll events are handled as mouse events), but for me this seemed necessary to fix this issue properly. As a result, JFXPanel had to be adjusted as well to comply to the changes in the EmbeddedSceneInterface, while its behavior should not have changed.

As horizontal mouse events cannot be synthesized via Display.post(Event) yet (an open issue for SWT), I did not add an automated test, but instead added a manual one (FXCanvasMouseWheelEventsTest). Therefore, this patch does not depend on the patch I provided earlier for JDK-8160325.

Best Regards,
Alexander