Panic when editor camera 2d viewport does not fit inside of bounds

[Dokkae6949]

trafficstars

PR #88 introduced a crash by using the Aabb2d::shrink method since that is not safe to use and will panic if the viewport does not fit inside the bounds. The PR removed the old custom implementation of the shrink method which removed the panic and handled it manually. This needs to be reverted.

Here the change in question