Prevent other inputs while dragging

[ConteZero]

This commit prevent other inputs to interfere with dragging operation.

[reduz]

This makes sense, but I believe it can break some scenarios (press some keys while dragging to adjust how the object will be dropped, we use this in some situations while dropping objects into the 2D/3D viewport). Maybe it should be optional when drag begins?

[ConteZero]

This makes sense, but I believe it can break some scenarios (press some keys while dragging to adjust how the object will be dropped, we use this in some situations while dropping objects into the 2D/3D viewport). Maybe it should be optional when drag begins?

I think there are two possible ways to solve this problem:

1. make it optional as you wrote
2. block all inputs by default and pass an array with the key codes to exclude from blocking

For 2) I don't know if adding an optional parameter to Control::get_drag_data will work, unfortunately it's been a long time since I've been working on this code, so I don't quite remember the details of how drag and drop is implemented.

Right now I don't have the time to work on it, so if anyone else wants to do it, they're welcome.

[Sauermann]

In its current form, this PR will interfere with the recently merged #68418