undocking and redocking scene view breaks rendered scene

[Doprez]

Release Type: GitHub

Version: master and 4.2.0.2043

Platform(s): Windows

Describe the bug
Currently in Master when you undock and the redock the scene view it causes the scene render to go blank. You have to reload the scene to get the view back to normal.

To Reproduce
Steps to reproduce the behavior:

1. drag the scene tab into its own window.
2. place the scene back into the dock

Expected behavior
Sceneview should not be blank after redocking to GameStudio.

Screenshots

Additional context
This works fine in the release 4.1.0.1948

[Eideren]

Closing this one in favor of #2161