Support partial type applications on inline methods

[gsps]

We currently crash on partial type applications of inline methods, e.g.:

object Foo {
  inline def f[S, T](x: S): T = ???
  def g(x: Int) = f[T = Any](x)
}

The immediate source of the problem lies in TypedTreeInfo.decomposeCall assuming that it will only encounter a single TypeApply.

I guess there's already some corresponding code to unscramble type arguments, so it hopefully shouldn't be too hard to adapt decomposeCall to do so too.