Previously when creating a CGPath with an arc, the path was wrong. It added a line when it wasn't necessary and when it was necessary it added a line to a wrong point.
Now CGPath works like in cocoa (If the specified path already contains a subpath, Quartz implicitly adds a line connecting the subpath’s current point to the beginning of the arc. If the path is empty, Quartz creates a new subpath with a starting point set to the starting point of the arc.)
Test app in Tests/Manual/CGPath/AppController.j