Use a valid gestures focal point when resetting a manager

[LukasPaczos]

Closes #14246.

The issue was twofold:

• we were resetting the gestures manager, and because of that recreating the internal listeners, with each component's options update
• we kept the scale/rotation focal points in a listeners' fields and re-validating them only during the start or progress of a gesture, however, when we've reset the gestures manager right between gesture's progress and finish methods, the focal point wouldn't have been initialized and resulted in an NPE

[tobrun]