[Ada] Spurious error on dynamic predicate in a generic context

[Ada] Spurious error on dynamic predicate in a generic context

This patch fixes a spurious error on the conformance checking between
the expression for an aspect analyzed at the freeze point of the type,
and the analysis of a copy of the expression performed at the end of the
enclosing list of declarationss. In a generic context the first may not
have been analyzed yet and this must be done before the conformance
check.

2019-07-03  Ed Schonberg  <schonberg@adacore.com>

gcc/ada/

	* sem_ch13.adb (Analyze_Attribute_Definition_Clause): No error
	message on attribute applied to a renaming when the renamed
	object is an aggregate (from code reading).
	(Check_Aspect_At_End_Of_Declarations): In a generic context
	where freeze nodes are not generated, the original expression
	for an aspect may need to be analyzed to precent spurious
	conformance errors when compared with the expression that is
	anakyzed at the end of the current declarative list.

gcc/testsuite/

	* gnat.dg/predicate5.adb, gnat.dg/predicate5.ads: New testcase.

From-SVN: r272969