Open Radar

 
Summary:
When setting the start position of an NSWindow in a storyboard, the actual position after launching the application is calculated before calculating the actually window's size based on its NSViewController and its content.

Steps to Reproduce:
1. Create a NSWindowController in a storyboard
2. Select the NSWindow and set its initial position to centered both horizontally and vertically
3. Make the windows NSViewController thin
4. Add a view to the NSViewController that constraints the width
5. Launch the application

Expected Results:
The thin window should be perfectly centered in the screen.

Actual Results:
The thin window is slightly off center horizontally, because the windows origin was calculated before calculating its width.

Notes:
You can fix this by putting the actual size of the window into the storyboard. Although this size may not always be known at this time.