[SCXML] Fail to parse 'delay' time with floating point values (W3C Test175)

Qt SCXML can not pass W3C mandatory test 175 because 'delayexpr=0.5s' can not be parsed

According to SCXML spec delay is 
A time designation as defined in CSS2 format as <number> (with or without a decimal point)

Issue may be reproduced with Qt SCXML Standard Compliance Tester with test175.scxml

 P.S. You are using qtscxml\tests\3rdparty\scion-tests\scxml-test-framework\test\w3c-ecma\test175.txml.scxml which does not correspond to original W3C mandatory test 175 because of modified time values