Description:
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is_resource($db) does not report MySQLi resource as valid resource type

Also, the MySQLi resource type is not mentioned as a resource type in ANNEX M.

Reproduce code:
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//after a valid connect where everything else works fine
if (is_resource($db))
  echo "OK";
else
  echo "NOT OK";




Expected result:
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OK

Actual result:
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NOT OK