refine modifiers handling in button press/release handler
refine modifiers handling in button press/release handler

Papapashu/freshplayerplugin,reuben/freshplayerplugin,Papapashu/freshplayerplugin,reuben/freshplayerplugin,grevutiu-gabriel/freshplayerplugin,reuben/freshplayerplugin,grevutiu-gabriel/freshplayerplugin,Papapashu/freshplayerplugin