What happened with PolygonCollider2D.GenerateFrom?

After downloading new Unity 4.3f my project stopped compiling, reporting a lot of errors. Is far as I can understand, some unity’s standard objects’ properties and methods just stopped being supported. For example, Sprite.size or PolygonCollider2D.GenerateFrom()
I can’t find any information about this stuff in the internet. There is no manual remarks, about being obsolet, or maybe limited pro version-only avaliability…
I’m very sorry to be so stupid if I posted in wrong place or if the answer is obvious, but if anione can explain to me what to do with this, I’l be very glad. Thank you in advance.

There never was a Sprite.size property or PolygonCollider2D.GenerateFrom() function, not in any publicly released version of Unity anyway. This is exactly why you should rarely if ever use undocumented functions, since they can and will be removed or changed at any time. Only use public and documented functions. Look in the docs if you’re ever unsure. If it’s not in the docs, it doesn’t (officially) exist.