Exceptions in _validate() method of FormFields not being propogated

[atbinf]

I just noticed that all the FormFields that override _validate() do not have their ValidationErrors (if the occur) caught and propagated to the "invalid" widget for display in the form. Example Widgets were the CheckBoxList and CheckBoxTable. To fix this I had to place the @twc.validation.catch_errors decorator on top of them. I noticed that in "dynforms" and core, they seem to pretty consistently do this for these methods when they are overridden. Any comments on this? Is this a bug in "forms" or in how the exceptions are being caught and handled in "core".