Description:
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The function handles urls of the form 'file:///C:\filename.ext' correctly, but when the scheme is not 'file' (e.g. 'cow:///C:\chicken.pie), it throws an error.

Would be nice if it behave the same way as parse_url() is useful for parsing the path to custom stream in ::stream_open().

Reproduce code:
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print_r(parse_url('file:///C:\index.php'));

print_r(parse_url('cow:///C:\index.php'));

Expected result:
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Array ( [scheme] => file [path] => /C:\index.php ) 
Array ( [scheme] => cow [path] => /C:\index.php ) 

Actual result:
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Array ( [scheme] => file [path] => /C:\index.php ) 
Warning: parse_url(cow:///C:\index.php): Unable to parse url in c:\www\test\parse_url.php on line 5