Support for --enable-malloc-tracing.

config/autoconf.mk.in

@@ -60,6 +60,7 @@ MOZ_JPROF       = @MOZ_JPROF@
 DETECT_WEBSHELL_LEAKS = @DETECT_WEBSHELL_LEAKS@
 BUILD_PROFILE	= @MOZILLA_GPROF@
 GC_LEAK_DETECTOR = @GC_LEAK_DETECTOR@
+NS_TRACE_MALLOC = @NS_TRACE_MALLOC@
 MOZ_MAIL_NEWS	= @MOZ_MAIL_NEWS@
 MOZ_BRPROF	= @MOZ_BRPROF@
 NO_UNIX_ASYNC_DNS = @NO_UNIX_ASYNC_DNS@