minor cleanups in is_dynamic_type

I noticed that gdbtypes.c:is_dynamic_type has some unneeded "break"s.
This patch cleans up the function a bit, removing those and removing
the switch's default case so that the end of the function is a bit
clearer.

2014-06-04  Tom Tromey  <tromey@redhat.com>

	* gdbtypes.c (is_dynamic_type): Remove unneeded "break"s.
handle VLA in a struct or union

It is valid in GNU C to have a VLA in a struct or union type, but gdb
did not handle this.

This patch adds support for these cases in the obvious way.

Built and regtested on x86-64 Fedora 20.
New tests included.

2014-06-04  Tom Tromey  <tromey@redhat.com>

	* ada-lang.c (ada_template_to_fixed_record_type_1): Use
	value_from_contents_and_address_unresolved.
	(ada_template_to_fixed_record_type_1): Likewise.
	(ada_which_variant_applies): Likewise.
	* value.h (value_from_contents_and_address_unresolved): Declare.
	* value.c (value_from_contents_and_address_unresolved): New
	function.
	* gdbtypes.c (is_dynamic_type, resolve_dynamic_type)
	<TYPE_CODE_STRUCT, TYPE_CODE_UNION>: New cases.
	(resolve_dynamic_struct, resolve_dynamic_union): New functions.

2014-06-04  Tom Tromey  <tromey@redhat.com>

	* gdb.base/vla-datatypes.exp: Add tests for VLA-in-structure and
	VLA-in-union.
	* gdb.base/vla-datatypes.c (vla_factory): Add vla_struct,
	inner_vla_struct, vla_union types.  Initialize objects of those
	types and compute their sizes.