Just upgraded my OS X to Yosemite, Android Device Chooser not showing device - what to do?
It seems to be a layout bug.
Drag one of the column headers in the device chooser where the device should be and change the column width and it magically appears!
You can also double click the device's row even when it's hidden, so you don't have to resize the column each time.
Another working solution is:
Disconnect and reconnect the device while the Android Device Chooser Popup is open.