logicalrep_message_type throws an error

Hi All,
logicalrep_message_type() is used to convert logical message type code
into name while prepared error context or details. Thus when this
function is called probably an ERROR is already raised. If
logicalrep_message_type() gets an unknown message type, it will throw
an error, which will suppress the error for which we are building
context or details. That's not useful. I think instead
logicalrep_message_type() should return "unknown" when it encounters
an unknown message type and let the original error message be thrown
as is.

-- 
Best Wishes,
Ashutosh Bapat