Description:
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The IntlChar::charFromName() method returns bool(false) when an invalid name is given.  According to the method signature, only integer values should be returned in this case.

The underlying C library returns "an undefined value if there is no such code point".  According to the RFC for IntlChar, the ICU functionality should "[follow] the ICU API as much as possible".

Furthermore, HHVM's implementation returns null in these cases.

I therefore feel that PHP should also return null in these cases instead of bool(false).  This would make it consistent with the ICU library and HHVM.

Test script:
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See https://3v4l.org/171NK or use the script below:

<?php
var_dump(IntlChar::charFromName("RECYCLING SYMBOL FOR TYPE-1 PLASTICS"));
var_dump(IntlChar::charFromName("sdfasdfasdfasdf"));