Description:
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when called on a function (not method) parameter, ReflectionParameter::getDeclaringClass() returns null.

The documentation should reflect this, as it currently implies that a ReflectionClass is always returned.

Expected result:
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public ReflectionClass|null ReflectionParameter::getDeclaringClass ( void )

Actual result:
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public ReflectionClass ReflectionParameter::getDeclaringClass ( void )