dwarf-reader: Simplify the canonicalization decision of types added to IR

dwarf-reader: Simplify the canonicalization decision of types added to IR

This is a long overdue clean-up.

Back in the day when we had no DWARF type DIE canonicalization, there
could be a LOT of IR types to be canonicalized.  To store set of those
types to be canonicalized, we the used the already existing
association type DIE offset -> IR types that we had, and so we only
had to store the DIE offsets of the IR types that we wanted to
canonicalize.  At canonicalization time, we'd walk the set of DIE
offsets we stored on the side, use the association type DIE offset ->
IR types to retrieve the IR type to canonicalize and we'd canonicalize
it.  This is somewhat complicated.

Now that we have DWARF DIEs canonicalization, the number of IR types
dropped significantly so this complicated scheme is no more warranted.

So this patch drops that indirection and stores the IR types to be
canonicalize into a vector of IR types and that's it.  Yay, less code.

	* src/abg-dwarf-reader.cc (maybe_canonicalize_type): Remove
	the overload that takes a Dwarf_Die* parameter.
	(operator++(die_source& source)): Likewise.
	(read_context::{types_to_canonicalize_,
	alt_types_to_canonicalize_,
	type_unit_types_to_canonicalize_}): Remove these data members
	of type vector<Dwarf_Off>.  (read_context::initialize): Remove
	invocations to alt_types_to_canonicalize_.clear(),
	type_unit_types_to_canonicalize_.clear(), and
	extra_types_to_canonicalize_.clear().
	(read_context::extra_types_to_canonicalize_): Rename this into
	read_context::types_to_canonicalize_, of type
	vector<type_base_sptr>.
	(read_context::types_to_canonicalize): Remove these member
	functions that take a parameter of type die_source.
	(read_context::extra_types_to_canonicalize): Rename this
	function into types_to_canonicalize.  It returns a type const
	vector<type_base_sptr>&.
	(read_context::schedule_type_for_late_canonicalization):
	Remove this overload that takes a type const Dwarf_Die*.  In
	the overload that takes a parameter const type_base_sptr
	however, rename the invocation to
	extra_types_to_canonicalize_.push_back(t) into
	types_to_canonicalize_.push_back(t).
	(read_context::canonicalize_types_scheduled): This doesn't
	take a die_source parameter anymore.  It now only cycles
	through the types retrieved by types_to_canonicalize() to
	canonicalize them.
	(read_context::add_late_canonicalized_types_stats): Remove the
	die_source parameter.  Use types_to_canonicalize().
	(read_context::perform_late_type_canonicalizing): Just call
	read_context::canonicalize_types_scheduled().
	(build_ir_node_from_die): Adjust calls to maybe_canonicalize_type.
	Also, really canonicalize the function type when a function decl is
	constructed.
	* tests/data/test-annotate/test13-pr18894.so.abi: Adjust.
	* tests/data/test-annotate/test15-pr18892.so.abi: Likewise.
	* tests/data/test-annotate/test20-pr19025-libvtkParallelCore-6.1.so.abi:
	Likewise.
	* tests/data/test-annotate/test21-pr19092.so.abi: Likewise.
	* tests/data/test-diff-pkg/nss-3.23.0-1.0.fc23.x86_64-report-0.txt:
	Likewise.
	* tests/data/test-read-dwarf/PR22122-libftdc.so.abi: Likewise.
	* tests/data/test-read-dwarf/test12-pr18844.so.abi: Likewise.
	* tests/data/test-read-dwarf/test13-pr18894.so.abi: Likewise.
	* tests/data/test-read-dwarf/test15-pr18892.so.abi: Likewise.
	* tests/data/test-read-dwarf/test16-pr18904.so.abi: Likewise.
	* tests/data/test-read-dwarf/test20-pr19025-libvtkParallelCore-6.1.so.abi:
	Likewise.
	* tests/data/test-read-dwarf/test21-pr19092.so.abi: Likewise.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>