metrics: Fixed compile-time warnings due to unused variables.

BUG=chromium-os:15040
TEST=built with gcc-4.6

Change-Id: Idf95c986e1eda79be735eeb4ff7c79e9a7eede60
Reviewed-on: http://gerrit.chromium.org/gerrit/569
Tested-by: Darin Petkov <petkov@chromium.org>
Reviewed-by: Chris Sosa <sosa@chromium.org>
diff --git a/metrics/metrics_daemon.cc b/metrics/metrics_daemon.cc
index 273fa60..e9031ab 100644
--- a/metrics/metrics_daemon.cc
+++ b/metrics/metrics_daemon.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -296,7 +296,6 @@
                                                DBusMessage* message,
                                                void* user_data) {
   Time now = Time::Now();
-  TimeTicks ticks = TimeTicks::Now();
   DLOG(INFO) << "message intercepted @ " << now.ToInternalValue();
 
   int message_type = dbus_message_get_type(message);