fixing Flash\Session::has() returning always true

[Izopi4a]

Hello!

• Type: bug fix
• Link to issue: Phalcon\Flash\Session::has return true when messages array is empty #15204

In raising this pull request, I confirm the following:

• I have read and understood the Contributing Guidelines
• I have checked that another pull request for this purpose does not exist
• I wrote some tests for this PR
• I have updated the relevant CHANGELOG
• I have created a PR for the documentation about this change

Small description of change:

I am basically reverting the changes on Flash\Session::has() from this PR https://github.com/phalcon/cphalcon/pull/13994/files

I don't agree with the way funtion is changed, feels like just a bug

Thanks

Something is wrong with the tests - the code looks OK

[Izopi4a]

i will check to see what is wrong, probably i broke something , changed the MR name to wip

[Izopi4a]

ok, so if the declarion in zephir is as followed:

public function test(string test = null) {
    var_dump(test);
}

test(); // will output string ""

[Jeckerson]

@Izopi4a Yep, just simulated in Zephir. For now we can specify var and check type if is string.

zephir-lang/zephir#2180

[niden]

Fixes #15353 (review)

@Izopi4a Thank you!