Move SystemMonitor to src/chrome/common....

ui/base/system_monitor/system_monitor_mac.mm

Index: ui/base/system_monitor/system_monitor_mac.mm
===================================================================
--- ui/base/system_monitor/system_monitor_mac.mm	(revision 0)
+++ ui/base/system_monitor/system_monitor_mac.mm	(working copy)
@@ -1,11 +1,13 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "app/system_monitor.h"
+#include "ui/base/system_monitor/system_monitor.h"
 
 #import <AppKit/AppKit.h>
 
+namespace ui {
+
 @interface SystemMonitorBridge : NSObject {
  @private
   SystemMonitor* systemMonitor_;  // weak
@@ -65,3 +67,5 @@
 void SystemMonitor::PlatformDestroy() {
   [system_monitor_bridge_ release];
 }
+
+}  // namespace ui