diagnostic-show-locus.c: handle fixits on lines outside the regular ranges

diagnostic-show-locus.c: handle fixits on lines outside the regular ranges

The diagnostic_show_locus implementation determines the set
of line spans that need printing based on the ranges within the
rich_location (in layout::calculate_line_spans).

Currently this doesn't take into account fix-it hints, and hence
we fail to print fix-it hints that are on lines outside of
those ranges.

This patch updates the implementation to take fix-it hints into
account when calculating the pertinent line spans, so that such fix-it
hints do get printed.  It also adds some validation, to ensure that
we don't attempt to print fix-its hints affecting a different source
file.

gcc/ChangeLog:
	* diagnostic-show-locus.c (class layout): Add field m_fixit_hints.
	(layout_range::intersects_line_p): New method.
	(test_range_contains_point_for_single_point): Rename to...
	(test_layout_range_for_single_point): ...this, and add testing
	for layout_range::intersects_line_p.
	(test_range_contains_point_for_single_line): Rename to...
	(test_layout_range_for_single_line): ...this,  and add testing
	for layout_range::intersects_line_p.
	(test_range_contains_point_for_multiple_lines): Rename to...
	(test_layout_range_for_multiple_lines): ...this,  and add testing
	for layout_range::intersects_line_p.
	(layout::layout): Populate m_fixit_hints.
	(layout::get_expanded_location): Handle the case of a line-span
	for a fix-it hint.
	(layout::validate_fixit_hint_p): New method.
	(get_line_span_for_fixit_hint): New function.
	(layout::calculate_line_spans): Add spans for fixit-hints.
	(layout::should_print_annotation_line_p): New method.
	(layout::print_any_fixits): Drop param "richloc", instead using
	validated fixits in m_fixit_hints.  Add "const" to hint pointers.
	(diagnostic_show_locus): Avoid printing blank annotation lines.
	(selftest::test_diagnostic_context::test_diagnostic_context):
	Initialize show_column and start_span.
	(selftest::test_diagnostic_context::start_span_cb): New static
	function.
	(selftest::test_diagnostic_show_locus_fixit_lines): New function.
	(selftest::diagnostic_show_locus_c_tests): Update for function
	renamings.  Call test_diagnostic_show_locus_fixit_lines.

libcpp/ChangeLog:
	* include/line-map.h (class fixit_remove): Remove stray decl.
	(fixit_hint::affects_line_p): Make const.
	(fixit_insert::affects_line_p): Likewise.
	(fixit_replace::affects_line_p): Likewise.
	* line-map.c (fixit_insert::affects_line_p): Likewise.
	(fixit_replace::affects_line_p): Likewise.

From-SVN: r239906