mouse right button would influence mouse event

[Herbert]

hi there,

my current version is 4.5.1, and I found a possible issue, if I do 
1. click mouse's left button on a sprite (fire onDown event)
2. keep the left button, then press the right button
3. keep the right button, then release the left button (onUp is not fired)
4. release the right button (onUp is still not fired)

so basically, the right click would influence mouse event, which as I tested is normal in version 4.3.5

thanks