ir: Make canonicalization stable wrt typedefs in fn return types

ir: Make canonicalization stable wrt typedefs in fn return types

In the grand scheme of things, two function return types can be equal
modulo typedefs.  Because those two function textual representations
are different, the two overall function types would end up having
different canonical types and thus, the two functions would be
considered as having different sub-types.  The harmless change pass
would then kick in and flag that change as harmless.  But then, "abidw
--abidiff" that is used for testing purposes would still be not happy.

This patch strips typedefs off of return types of function types when
the string representation is to be used for internal (e.g, type
canonicalization) purposes.

The fix for this change uncovered another issue:

When setting the naming typedefs for an (anonymous) C++ class, the
qualified name of the class was wrongly being set to the qualified
name of the typedef.  Only the name of the class should be affected,
in essence.  The qualified name would, ONLY as a result of the name
change, be adjusted.

This patch fixes those issues and adjusts the test suite accordingly.

	* src/abg-ir.cc (get_function_type_name, get_method_type_name):
	When the function type name is for internal purposes, strip
	potential typedefs off.
	(equal): In the overload for function_type, strip potential
	typedefs off of return types before comparing them.
	(decl_base::set_naming_typedef): Properly adjust the qualified
	name of the type to which a naming typedef is being set.
	* tests/data/test-alt-dwarf-file/libstdc++/libstdc++-report.txt:
	New reference test output.
	* tests/data/test-alt-dwarf-file/libstdc++/usr/lib/debug/usr/lib64/libstdc++.so.6.0.30-12.1.1-1.fc37.x86_64.debug:
	New binary test input.
	* tests/data/test-alt-dwarf-file/libstdc++/usr/lib64/libstdc++.so.6.0.30:
	New binary test input.
	* tests/data/Makefile.am: Add the new test material to source
	distribution.
	* tests/data/test-annotate/test15-pr18892.so.abi: Adjust.
	* tests/data/test-annotate/test17-pr19027.so.abi: Likewise.
	* tests/data/test-annotate/test21-pr19092.so.abi: Likewise.
	* tests/data/test-read-dwarf/PR25007-sdhci.ko.abi: Likewise.
	* tests/data/test-read-dwarf/test-libaaudio.so.abi: Likewise.
	* tests/data/test-read-dwarf/test-libandroid.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/test17-pr19027.so.abi: Likewise.
	* tests/data/test-read-dwarf/test21-pr19092.so.abi: Likewise.

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