Expression<TDelegate>.Update shouldn't be annotated to return a nullable value

[roji]

Expression.Update is annotated to return nullable, although it doesn't to actually return null in any code path. In general, Update methods in System.Linq.Expressions never turn null.

/cc @cston @smitpatel @ajcvickers

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Details

Issue Details

Description:	Expression.Update is annotated to return nullable, although it doesn't to actually return null in any code path. In general, Update methods in System.Linq.Expressions never turn null. /cc @cston
Author:	roji
Assignees:	-
Labels:	area-System.Linq.Expressions, bug
Milestone:	-