Gori_compute inherits from gimple_outgoing_range.

Gori_compute inherits from gimple_outgoing_range.

Make gimple_outgoing_range a base class for the GORI API, and provide
base routines returning false.   gori_compute inherits from
gimple_outgoing_range and no longer needs it as a private member.
Rename outgoing_edge_range_p to edge_range_p.

	* gimple-range-cache.cc (ranger_cache::ranger_cache): Adjust
	m_gori constructor.
	(ranger_cache::edge_range): Use renamed edge_range_p name.
	(ranger_cache::range_from_dom): Likewise.
	* gimple-range-edge.h (gimple_outgoing_range::condexpr_adjust): New.
	(gimple_outgoing_range::has_edge_range_p): New.
	(gimple_outgoing_range::dump): New.
	(gimple_outgoing_range::compute_operand_range): New.
	(gimple_outgoing_range::map): New.
	* gimple-range-fold.cc (fur_source::register_outgoing_edges ): Use
	renamed edge_range_p routine
	* gimple-range-gori.cc (gori_compute::gori_compute): Adjust
	constructor.
	(gori_compute::~gori_compute): New.
	(gori_compute::edge_range_p): Rename from outgoing_edge_range_p
	and use inherited routine instead of member method.
	* gimple-range-gori.h (class gori_compute): Inherit from
	gimple_outgoing_range, adjust protoypes.
	(gori_compute::outgpoing): Delete.
	* gimple-range-path.cc (path_range_query::compute_ranges_in_block): Use
	renamed edge_range_p routine.
	* tree-ssa-loop-unswitch.cc (evaluate_control_stmt_using_entry_checks):
	Likewise.