Description:
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The php_filter_int function located in /[svn]/php/php-src/trunk/ext/filter/logical_filters.c does not allow thousand separators in the provided value to valide.

Most countries allows using of thousand separators, so if the function is not usable in validating user input.

Please provide support for thousand separators in the sense of FILTER_FLAG_ALLOW_THOUSAND flag for php_filter_float function and Request #51368. 

Test script:
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var_dump(filter_var('1 000', FILTER_VALIDATE_INT, array('flags' => FILTER_FLAG_ALLOW_THOUSAND, 'options' => array('thousand' => ' '))));

Expected result:
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int(1000)

Actual result:
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bool(false)