When switching shading between material preview and solid modes, the
world reflective light could become uninitialized. The reason was that
the world was only updated when they actually changed. When switching
it might not be the case that the world changed and the world probe
wasn't uploaded to the texture.
This fix will reduce the locations where this information was stored
(removing the `do_world_update` attribute in `ReflectionProbeModule`).
It also doesn't reset the `do_render` flag during syncing, but post-
pone it to the actual drawing.
Jeroen Bakker