AbstractConditionViewHelper should not use ViewHelper name to decide if a childNode is a "then" or "else" node

[sascha-egerer]

Currently, the AbstractConditionViewHelper relies on the ending of the viewhelper name if it is a "then" or "else" node.

Fluid/src/Core/ViewHelper/AbstractConditionViewHelper.php

Lines 119 to 127 in 0a39cd6

	if ($childNode instanceof ViewHelperNode
	&& str_ends_with($childNode->getViewHelperClassName(), 'ThenViewHelper')) {
	$data = $childNode->evaluateChildNodes($this->renderingContext);
	return $data;
	}
	if ($childNode instanceof ViewHelperNode
	&& str_ends_with($childNode->getViewHelperClassName(), 'ElseViewHelper')) {
	$elseViewHelperEncountered = true;
	}

This could produce unexpected side effects as a "WhatElseViewHelper" would be interpreted as an else node but is actually just a normal viewhelper.
Possible test case could be (I’ve not really validated the faulty behaviour yet but just stumbled over the code in #1052 (comment)).

<f:if condition="{verdict}">
   <my:whatElse>hello<my:whatElse>
</f:if>