Merge handle_inferior_event and handle_inferior_event_1

I noticed that handle_inferior_event is just a small wrapper that
frees the value chain.  This patch replaces it with a
scoped_value_mark, reducing the number of lines of code here.

Regression tested on x86-64 Fedora 29.

gdb/ChangeLog
2019-03-20  Tom Tromey  <tromey@adacore.com>

	* infrun.c (handle_inferior_event): Rename from
	handle_inferior_event_1.  Create a scoped_value_mark.
	(handle_inferior_event): Remove.

Author: tromey

gdb/ChangeLog

@@ -1,3 +1,9 @@
+2019-03-20  Tom Tromey  <tromey@adacore.com>
+
+	* infrun.c (handle_inferior_event): Rename from
+	handle_inferior_event_1.  Create a scoped_value_mark.
+	(handle_inferior_event): Remove.
+
 2019-03-19  Tom Tromey  <tromey@adacore.com>
 
 	* mi/mi-interp.c (mi_on_normal_stop_1): Only show displays once.

gdb/infrun.c

@@ -4591,8 +4591,13 @@ handle_no_resumed (struct execution_control_state *ecs)
    once).  */
 
 static void
-handle_inferior_event_1 (struct execution_control_state *ecs)
+handle_inferior_event (struct execution_control_state *ecs)
 {
+  /* Make sure that all temporary struct value objects that were
+     created during the handling of the event get deleted at the
+     end.  */
+  scoped_value_mark free_values;
+
   enum stop_kind stop_soon;
 
   if (ecs->ws.kind == TARGET_WAITKIND_IGNORE)
@@ -5189,22 +5194,6 @@ Cannot fill $_exitsignal with the correct signal number.\n"));
     }
 }
 
-/* A wrapper around handle_inferior_event_1, which also makes sure
-   that all temporary struct value objects that were created during
-   the handling of the event get deleted at the end.  */
-
-static void
-handle_inferior_event (struct execution_control_state *ecs)
-{
-  struct value *mark = value_mark ();
-
-  handle_inferior_event_1 (ecs);
-  /* Purge all temporary values created during the event handling,
-     as it could be a long time before we return to the command level
-     where such values would otherwise be purged.  */
-  value_free_to_mark (mark);
-}
-
 /* Restart threads back to what they were trying to do back when we
    paused them for an in-line step-over.  The EVENT_THREAD thread is
    ignored.  */