[gjs/wip/js24] Update another JS_Call*Tracer, not sure if this is actually the right thing to do here though.

[Tim Lunn <timl src gnome org>]

commit 244e253fb19c7a29b0e33f1dfca33ae56300b9e8
Author: Tim Lunn <tim feathertop org>
Date:   Sat Sep 28 14:37:23 2013 +1000

    Update another JS_Call*Tracer, not sure if this is actually the right
    thing to do here though.

 gi/keep-alive.cpp |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/gi/keep-alive.cpp b/gi/keep-alive.cpp
index bf89d04..8eee636 100644
--- a/gi/keep-alive.cpp
+++ b/gi/keep-alive.cpp
@@ -124,7 +124,8 @@ trace_foreach(void *key,
         jsval val;
         JS_SET_TRACING_DETAILS(tracer, NULL, "keep-alive", 0);
         val = OBJECT_TO_JSVAL(child->child);
-        JS_CallTracer(tracer, JSVAL_TO_TRACEABLE (val), JSTRACE_OBJECT);
+        g_assert (JSVAL_TO_TRACEABLE (val));
+        JS_CallValueTracer(tracer, &val, "keep-alive::val");
     }
 }