Fixed KDBusMatches bug.

Missing comma in array definition caused metrics_daemon to fail.
Metrics_daemon would use a lot of CPU when broken.

Review URL: http://codereview.chromium.org/2767003
diff --git a/metrics/metrics_daemon.cc b/metrics/metrics_daemon.cc
index 5ccc694..70c0748 100644
--- a/metrics/metrics_daemon.cc
+++ b/metrics/metrics_daemon.cc
@@ -62,7 +62,7 @@
 
   "type='signal',"
   "interface='" DBUS_IFACE_POWER_MANAGER "',"
-  "path='/'"
+  "path='/'",
 
   "type='signal',"
   "sender='org.chromium.SessionManager',"