There is no Cocoa local autorelease pool for each QApplication event loop iteration.

Local autorelease pools are provided within NSApplication event handling, but Qt events which are delivered via CFRunLoop source do not have one.

This is an unexpected behaviour and may cause leaks. The only way autorelease objects are currently released is when application modal window is shown and NSApp runloop is interrupted, which is not a proper way.

Proposed patch is attached.