Camera projection default viewport missmatch

[mtszkarbowiak]

Issue description:

Default camera projection viewport does not align with the main viewport.

Example:

The following code does not work:

Camera.ProjectPoint(Target.Position, out origin);
origin += ScreenOffset;

But this code works (Assuming the control takes space of the entire viewport):

var viewport = Camera.Viewport;
viewport.Size = Control.Size; // Override the size
Camera.ProjectPoint(Target.Position, out origin, ref viewport);
origin += ScreenOffset;

Flax version:

1.7, 1.8, master