What problem does this solve or what need does it fill?

After #15685 it became inconvenient to mock inputs. On 0.14 we could call set_pressed or set. But these methods are no longer exposed.

It's still possible to do this by sending events, but it's inconsistent with the rest of the input and not very ergonomic.

What solution would you like?

I would like to bring back set_pressed and set.

Additional context

There is a similar issue regardless gamepad creation that predates the gamepads rework: #4911. Could be solved by adding a constructor for Gamepad component.