ecma_parser: add space after 'class' and 'function' keywords

• to support case where these keywords are used in parameters or variables
• side effect, anonymous functions are no longer detected. But it's not a big deal (and probably better) because without name, it's not very useful to display them

NOTE: This parser must be rewritten by using regexp like others ones to be able to parse more correctly source code. It explain why the sample file is not correctly parsed (aka Class2 and all global functions see as members of Class1`). This fix is only a quick fix for this specific case.