Add the implementation skeleton for systeminfo.cpu API

chrome/common/extensions/api/experimental_systeminfo_cpu.idl

+// Copyright (c) 2012 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.
+
+// File-level comment to appease parser. Eventually this will not be necessary.
+namespace experimental.systeminfo.cpu {
+
+  dictionary CpuCoreInfo {
+    // Indicates the load of CPU core, as a number between 0 and 100

[Mihai Parparita -not on Chrome, 2012/08/10 20:24:56]

Nit: comments end with a period (applies to the whole file).

[Hongbo Min, 2012/08/12 14:22:44]

Done.

+    long load;
+  };
+  
+  dictionary CpuInfo {
+    // The array of the CPU processors in the system
+    CpuCoreInfo[] cores;
+  };
+
+  dictionary ChangeInfo {
+    // The index of CPU core on which the load has been changed
+    long index;
+    // The changed load
+    long load;
+  };  
+
+  callback CpuInfoCallback = void (CpuInfo prop);
+  callback CpuUpdateCallback = void (ChangeInfo info);
+  
+  interface Functions {
+    // Get CPU property 
+    static void get(CpuInfoCallback callback);
+
+    // Set the update interval, in seconds
+    static void setUpdateInterval(long interval);
+  };
+  
+  interface Events {
+    // Fired when CPU info is updated. Default update interval is 1 seconds
+    // |info|  : Contains the changed information of Cpu core
+    static void onUpdated(ChangeInfo info);
+  };
+};