Removing requirement to restart game after applying changes to mouse focus option. The setting now defaults to 'false' as it is likely to be disruptive to players who are used to the usual behaviour in windowed mode.

OpenRA.Game/IGraphicsDevice.cs

@@ -58,6 +58,9 @@ namespace OpenRA
 		void DisableDepthBuffer();
 
 		void SetBlendMode(BlendMode mode);
+
+		void GrabWindowMouseFocus();
+		void ReleaseWindowMouseFocus();
 	}
 
 	public interface IVertexBuffer<T>