go-gcc.cc (class Bvariable): Remove Gcc_tree parent class.

go-gcc.cc (class Bvariable): Remove Gcc_tree parent class.

	* go-gcc.cc (class Bvariable): Remove Gcc_tree parent class.  Add
	t_ and orig_type_ fields.  Add new two parameter constructor.  Add
	get_tree and get_decl methods.
	(Gcc_backend::var_expression): Pass location to var get_tree.
	(Gcc_backend::global_variable): Don't add VIEW_CONVERT_EXPR.  Use
	two parameter constructor for Bvariable.
	(Gcc_backend::global_variable_set_init): Don't remove
	VIEW_CONVERT_EXPR.  Use var get_decl, not get_tree.
	(Gcc_backend::write_global_definitions): Likewise.
	(Gcc_backend::init_statement): Call var get_decl, not get_tree.
	(Gcc_backend::block): Likewise.
	(Gcc_backend::implicit_variable_set_init): Likewise.
	(Gcc_backend::immutable_struct_set_init): Likewise.
	(Gcc_backend::function_set_parameters): Likewise.

From-SVN: r231894