Regression from 5.9: Multiple issues with event handling in QMacCocoaViewContainer

Find the demo project attached. It has a QMacCocoaViewContainer in the main window, and NSView inside the container. The NSView paints its entire area red for visual reference. The mouse events and resize events are logged with qDebug().

Here's are the issues I've found:

1. No mouse events are registered in the QMacCocoaViewContainer (move, press).
2. The resize events are not passed through to the underlying NSView: if you resize the window to be larger than its original size, you will at some point find that the red rectangle inside (the NSView area) has a fixed size and does not resize with the main window.
3. The paint events are not passed through to the NView: if you bring some other window to front, and then switch back to the test program, you will find that its window is blank white. If you resize the window, then the NSView will be re-painted red properly.

All these issues are a regression from Qt 5.9.4.