Add search_flags to expand_symtabs_matching

Add search_flags to expand_symtabs_matching

This adds a block search flags parameter to expand_symtabs_matching.
All callers are updated to search both the static and global blocks,
as that was the implied behavior before this patch.

This is a step toward replacing lookup_symbol with
expand_symtabs_matching.

gdb/ChangeLog
2021-04-17  Tom Tromey  <tom@tromey.com>

	* symtab.c (global_symbol_searcher::expand_symtabs)
	(default_collect_symbol_completion_matches_break_on): Update.
	* symmisc.c (maintenance_expand_symtabs): Update.
	* symfile.h (expand_symtabs_matching): Add search_flags
	parameter.
	* symfile.c (expand_symtabs_matching): Add search_flags
	parameter.
	* symfile-debug.c (objfile::expand_symtabs_matching): Add
	search_flags parameter.
	* quick-symbol.h (struct quick_symbol_functions)
	<expand_symtabs_matching>: Add search_flags parameter.
	* python/py-symbol.c (gdbpy_lookup_static_symbols): Update.
	* psymtab.c (recursively_search_psymtabs)
	(psymbol_functions::expand_symtabs_matching): Add search_flags
	parameter.
	* psympriv.h (struct psymbol_functions) <expand_symtabs_matching>:
	Add search_flags parameter.
	* objfiles.h (struct objfile) <expand_symtabs_matching>: Add
	search_flags parameter.
	* linespec.c (iterate_over_all_matching_symtabs): Update.
	* dwarf2/read.c (struct dwarf2_gdb_index)
	<expand_symtabs_matching>: Add search_flags parameter.
	(struct dwarf2_debug_names_index) <expand_symtabs_matching>: Add
	search_flags parameter.
	(dw2_map_matching_symbols): Update.
	(dw2_expand_marked_cus, dw2_expand_symtabs_matching)
	(dwarf2_gdb_index::expand_symtabs_matching): Add search_flags
	parameter.
	(dw2_debug_names_iterator): Change block_index to search flags.
	<m_block_index>: Likewise.
	(dw2_debug_names_iterator::next)
	(dwarf2_debug_names_index::lookup_symbol)
	(dwarf2_debug_names_index::expand_symtabs_for_function)
	(dwarf2_debug_names_index::map_matching_symbols)
	(dwarf2_debug_names_index::map_matching_symbols): Update.
	(dwarf2_debug_names_index::expand_symtabs_matching): Add
	search_flags parameter.
	* ada-lang.c (ada_add_global_exceptions)
	(collect_symbol_completion_matches): Update.