Rock does not type check arguments of generic type that was infered in the same call

[alexnask]

An example should be simpler to understand:

// This compiles
Foo: class <T> {
    init: func(a, b: T)
}

foo := Foo new(1, "lol")

// This too
f: func <T> (a, b: T)

f("what", 12)

[fasterthanlime]

Looks like it was fixed at the same time as #825