ID 379496 - Parameter widgets in the Project Settings tab should avoid accepting mouse scroll wheel events without mouse focus

Problem summary

When adding new variables to the global Graph State Variable parameter interface in the Project Settings tab, the empty parameter accepts mouse scroll input without mouse focus. Note that after an initial value has been passed into the parameter interface, it no longer accepts scroll input without focus (the intended behavior).

A parameter has focus when you've clicked on it. That's when scrolling should affect the value (if it's a number). If you're just hovering over the parameter with your mouse, scrolling shouldn't change the parameter value.

Customer reported version
katana.3.0v6

Customer reported platform
centos6

Steps to reproduce

1) In the Project Settings tab, add multiple global graph state variables (until the UI is scroll-able).

2) Still in the Project Settings tab, scroll over the parameter values.

Workaround
No known workaround.

Reproduced by QA
This bug has been reproduced in:

Earliest version tested
Katana 2.5v5

- This feature did not exist before this version
- Katana 2.5v5 introduced the ability to step through parameter values using the keyboard arrow keys or the mouse scroll wheel.

Expected behavior
When scrolling on a parameter value without focus, the values should not change. When applicable, the UI should scroll only.

Actual behavior
When scrolling on a parameter value without focus, the values change and the UI does not scroll.