c++: class array new checking [PR104084]

c++: class array new checking [PR104084]

My patch for PR20040 made us stop exiting early from build_new_1 in
cases of trivial initialization if there's a class operator delete; as a
result, code later in the function needs to handle this case properly.

	PR c++/104084
	PR c++/20040

gcc/cp/ChangeLog:

	* init.cc (build_new_1): Only pull out TARGET_EXPR_INITIAL if
	alloc_expr is a TARGET_EXPR.

gcc/testsuite/ChangeLog:

	* g++.dg/init/new50.C: New test.