QML Crash with invalid picture address.

With Qt5 beta1 release version.
1. Set image element cache = false
2. Load a picture with invalid address in qml.
set QML image element.source = invaild picture address, for example "http://www.google.com"
3. We have 5 pictures to be displayed(other 4 could be valid or invalid), add a button to switch pictures quickly in a loop, when it goes to the invalid source on the screen, the app will crash after several clicks.