Description:
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intl 51.2 errors out when trying to create a pattern with named parameter {n} (or any other name) used in "selectordinal". It should work as in case with "plural" and all other patterns.

Positional placeholder {0} works as expected.

Test script:
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<?php
$m = new MessageFormatter('en', '{n, selectordinal, one{#-one} two{#-two} few{#-few} other{#-other}}');
var_dump($m->format(array('n' => 42)));

Expected result:
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42-two

Actual result:
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{n, selectordinal, one{#-one} two{#-two} few{#-few} other{#-other}}