Fix -fsave-optimization-record ICE (PR tree-optimization/87025)

Fix -fsave-optimization-record ICE (PR tree-optimization/87025)

PR tree-optimization/87025 reports an ICE within
-fsave-optimization-record's optrecord_json_writer.

The issue is that dump_context::begin_scope creates an optinfo
of kind OPTINFO_KIND_SCOPE, but fails to call
dump_context::end_any_optinfo, so the optinfo for the scope remains
pending.

The JSON writer would normally push a JSON array for the "scope" optinfo
when the latter is emitted.  However, if a dump_* call happens that
doesn't flush the "scope" optinfo e.g. dump_printf (as opposed to
dump_printf_loc), that dump_ call is added to the pending optinfo, and
optinfo::handle_dump_file_kind changes the pending optinfo's m_kind
(e.g. to OPTINFO_KIND_NOTE).  Hence when the pending optinfo is
eventually emitted, it isn't OPTINFO_KIND_SCOPE anymore, and hence
the JSON writer doesn't create and push a JSON array for it, leading
to dump_context's view of scopes getting out-of-sync with that of
the JSON writer's.

Later, dump_context::end_scope unconditionally tries to pop the JSON scope
array, but no JSON scope array was added, leading to an assertion
failure (or crash).

The fix is to call dump_context::end_any_optinfo immediately after
creating the scope optinfo, so that it is emitted immediately, ensuring
that the JSON writer stays in-sync with the dump_context.

gcc/ChangeLog:
	PR tree-optimization/87025
	* dumpfile.c (dump_context::begin_scope): Call end_any_optinfo
	immediately after creating the scope optinfo.
	(selftest::test_pr87025): New function.
	(selftest::dumpfile_c_tests): Call it.
	* optinfo-emit-json.cc (optrecord_json_writer::pop_scope): Assert
	that we're not popping the top-level records array.
	* optinfo.cc (optinfo::handle_dump_file_kind): Assert that we're
	not changing the kind of a "scope" optinfo.

gcc/testsuite/ChangeLog:
	PR tree-optimization/87025
	* gcc.dg/pr87025.c: New test.

From-SVN: r266280