Lucas Gandel authored Apr 09, 2018 and Mathieu Westphal (Kitware) committed May 29, 2018

Prepend "cmd /c " to the execute_process command on windows. This
ensures that paraview's GUI will be shown during the test and all
elements get rendered.
This is required to ensure proper mouse interactions with VTK charts.

Force widget to be valid before pqCoreBasicApp screenshot
The arbitrary timer duration in pqCoreBasicApp does not ensure that
the QVTKOpenGLWidget had time to become valid for rendering.
Recursively restart the timer untill the widget is valid.

Improve ColorEditorVolumeControls XML test command

Add NativeWidget test