Viewport 2.0 preview doesn't include new geo when in legacy viewport

[BigRoy]

Problem

When the visible modelPanels currently all are legacy viewport renderers and extra objects are created (e.g. duplicating some) and then using the preview in the interface that forces it to render a Viewport 2.0 playblast the newly created objects are not present in the preview.

It seems viewport 2.0 doesn't know about these new objects until the Viewport 2.0 has been activated.

This sounds related to abstractfactory/maya-capture#60

To reproduce:

• Set viewports to legacy
• Open capture gui
• With override viewport options and HQ: Viewport 2.0 + AA options enabled create a preview
• Duplicate and move around some geometry
• Click preview image to update

The newly created objects will not be present, until you've switched to Viewport 2.0.

[BigRoy]

Testing this with the version from #15 I haven't been able to reproduce this bug. (Testing in Maya 2016 EXT 1 SP6). I'm considering this fixed.