Copying notes from parent issue:

unboxedType

spec: IAE when the "given type has no unboxing conversion"

actual: matches spec

expected: fine, but could be more explicit that there will always be an IAE for non-DeclaredTypes.

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getWildcardType

spec: IAE if an input TypeMirror is "not valid"

actual: IAE for PrimitiveType, WildcardType, UnionType, ExecutableType, and NoTypes; no error for ErrorTypes.

expected: behavior is fine, but spec should be more clear -- that is, IAE for all non-ReferenceTypes.