Scala style properties unnecessarily require a field with the same name

The changes introduced with TAP5-1064 allow Scala-style properties to be used from components without the need for Java-style getters and setters. The implementation currently requires a field of the same name as the property to exist on the bean, which is unfortunate.

This works:

var value: String = _

<input ... t:value="value" />

This does not:

def value(): String = ...
def value_=(value: String)

<input ... t:value="value" />

A class which delegates property access to a backing bean is not recognized by PropertyAccessImpl as having any valid properties; the same is the case when the field has a different name than the property.

Possible workarounds include a dead field in the value class to satisfy the condition in PropertyAccessImpl, and adding Java-style getters and setters for the property.