CentOS 7 / GTX 1070
Broken: 2.79 and older
Short description of error
view2d.view_to_region() function seems not working when position is outside the view. It always returns 12000 value and makes some shape impossible, like mapping a range in the timeline that is hided by zooming or panning, keep displaying something on VSE or ImageEditor while zooming and make the selected coordinate outside the view.
Exact steps for others to reproduce the error
Open the .blend file, execute the script and try moving the windows on the right to see issue happens.