Move systemInfo.cpu API out out experimental namespace.

chrome/common/extensions/api/system_info_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 {
+namespace systemInfo.cpu {
 
   dictionary CpuInfo {
     // The number of logical processors.
     long numOfProcessors;
     // The architecture name of the processors.
     DOMString archName;
     // The model name of the processors.
     DOMString modelName;
   };
 
   dictionary CpuUpdateInfo {
     // The average usage percent of all processors, as a number 
     // between 0 and 100.
     double averageUsage;
     // The CPU usage array for each logic processor.
     double[] usagePerProcessor;
   };
 
   callback CpuInfoCallback = void (CpuInfo info);
   
   interface Functions {
     // Get CPU information.

[asargent_no_longer_on_chrome, 2013/05/30 19:14:00]

nit: can we include something here about whether this queries the state or
returns a cached value?

[Tim Song, 2013/05/31 01:08:35]

This function gets basic CPU information using base::SysInfo, and doesn't cache
anything.

     static void get(CpuInfoCallback callback);
   };
 
   interface Events {
     // Fired periodically to report CPU history usage information. The default
     // period interval is 1 seconds.

[asargent_no_longer_on_chrome, 2013/05/30 19:14:00]

I don't understand this comment about the "default" period interval, since it
doesn't seem that developers can change it. Can we be more precise here?

I can definitely see how it would be interesting to be able to specify an
interval, but the API style might need to change to be more like chrome.alarms. 

[Tim Song, 2013/05/31 01:08:35]

From what I understand, we're planning on removing this function as it's not
being used anywhere.

[asargent_no_longer_on_chrome, 2013/05/31 18:31:32]

Any reason not to just remove it now? In any event, since we are controlling
access to the entire API via the whitelist it's ok to leave in if we need to, we
just need to make sure not to make it generally available on stable channel if
we know we plan to remove it in the future. 

[Tim Song, 2013/05/31 19:29:03]

I was planning on doing this after this changelist as there is quite a bit of
code to be removed.

     static void onUpdated(CpuUpdateInfo info);
   };
 };