Fix tab bar size calculation to account for tab margin
Fix tab bar size calculation to account for tab margin

baldurk/renderdoc,baldurk/renderdoc,etnlGD/renderdoc,TurtleRockStudios/renderdoc_public,michaelrgb/renderdoc,googlestadia/renderdoc,etnlGD/renderdoc,michaelrgb/renderdoc,baldurk/renderdoc,Zorro666/renderdoc,baldurk/renderdoc,baldurk/renderdoc,michaelrgb/renderdoc,googlestadia/renderdoc,michaelrgb/renderdoc,etnlGD/renderdoc,Zorro666/renderdoc,TurtleRockStudios/renderdoc_public,googlestadia/renderdoc,michaelrgb/renderdoc,Zorro666/renderdoc,googlestadia/renderdoc,Zorro666/renderdoc,Zorro666/renderdoc,TurtleRockStudios/renderdoc_public,etnlGD/renderdoc,googlestadia/renderdoc,TurtleRockStudios/renderdoc_public,TurtleRockStudios/renderdoc_public,baldurk/renderdoc,Zorro666/renderdoc,TurtleRockStudios/renderdoc_public,etnlGD/renderdoc,etnlGD/renderdoc,googlestadia/renderdoc