c++: improve debug_tree for templated types/decls
gcc/cp/ChangeLog:
* ptree.cc (cxx_print_decl): Check for DECL_LANG_SPECIFIC and
TS_DECL_COMMON only when necessary. Print DECL_TEMPLATE_INFO
for all decls that have it, not just VAR_DECL or FUNCTION_DECL.
Also print DECL_USE_TEMPLATE.
(cxx_print_type): Print TYPE_TEMPLATE_INFO.
<case BOUND_TEMPLATE_TEMPLATE_PARM>: Don't print TYPE_TI_ARGS
anymore.
<case TEMPLATE_TYPE/TEMPLATE_PARM>: Print TEMPLATE_TYPE_PARM_INDEX
instead of printing the index, level and original level
individually.