Description:
------------
I was trying to mock a ZF class using PHPUnit which has a method that hints a 
parameter as "self" rather than using the class name. 
ReflectionParameter::getClass() returns the correct class name, however, there 
is no way to find out that the actual method signature used "self" rather than 
the class name.

See:
https://github.com/sebastianbergmann/phpunit-mock-objects/issues/107
https://github.com/zendframework/zf2/issues/2977

While this behaviour is expected, using echo() on the parameters outputs 
"Parameter #0 [ <required> self $merge ]" (we can see it's not "Config" but 
"self") while using getClass() returns the "self" turned into ReflectionClass. 
Could another method be added to ReflectionParameter that returns the raw "type 
hint", i.e. "self" so that method's signature can be properly replicated for 
testing?

Test script:
---------------
class Config {
public function merge(self $merge){
}
}

$ref = new ReflectionMethod("Config", "merge");
echo current($ref->getParameters()) , " ", current($ref->getParameters())->getClass()->name;