Crash: parsing generic factory method with type parameter bound

[DartBot]

This issue was originally filed by ief...@unipro.ru

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Consider the following test:

class M<T> {
  factory M<T extends C>() {}
}

main() {

}

This produces the following error:
runtime/vm/class_finalizer.cc:276: error: expected: !lib.IsNull()

Dart VM r2175

Set owner to @crelier.
Added Area-VM, Triaged labels.

[crelier]

Fixed in r2208.

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Added Fixed label.