Touchscreen pinch to zoom

[MikeFarrington]

The app supports pinch-to-zoom using a trackpad, but not a touchscreen.

When trying to view the timeline for a large application from my laptop, which has a buttonless touchpad, scrolling around the timeline was a real pain. I found that using the touchscreen on my laptop to drag and scroll the timeline was great, but I couldn't do two-finger pinch-to-zoom via the touchscreen. That only worked from the trackpad.

I may try to add this. I just wanted to bring it up as a discussion topic first.