Fix draggable for layer outside of Framer.CurrentContext

[nvh]

Reproduce:

• See the following example: http://share.framerjs.com/q6vbjhkoajuv/
• Try dragging around the red and the green layers

Expected:

Both the red and the green layer can be dragged normally

Observed:

The red layer that is outside of Framer.CurrentContext moves around to quickly (relative to the device scale)

Remarks:

This is due to the conversion of the eventPoint to Framer.CurrentContext that happens here: https://github.com/koenbok/Framer/blob/52589798b44e3c7e3f11928432a1c0757ddcb2fb/framer/GestureInputRecognizer.coffee#L330

[koenbok]

We should probably fix this in layer.emit because that is where the event and context come together.