Add source column to chrome://policy showing the origins of policies.

components/policy/core/common/policy_loader_ios.mm

 // Copyright 2014 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 "components/policy/core/common/policy_loader_ios.h"
 
 #import <Foundation/Foundation.h>
 #import <UIKit/UIKit.h>
 
 #include "base/bind.h"
@@ skipping 159 matching lines @@
 // static
 void PolicyLoaderIOS::LoadNSDictionaryToPolicyBundle(NSDictionary* dictionary,
                                                      PolicyBundle* bundle) {
   // NSDictionary is toll-free bridged to CFDictionaryRef, which is a
   // CFPropertyListRef.
   scoped_ptr<base::Value> value =
       PropertyToValue(static_cast<CFPropertyListRef>(dictionary));
   base::DictionaryValue* dict = NULL;
   if (value && value->GetAsDictionary(&dict)) {
     PolicyMap& map = bundle->Get(PolicyNamespace(POLICY_DOMAIN_CHROME, ""));
-    map.LoadFrom(dict, POLICY_LEVEL_MANDATORY, POLICY_SCOPE_MACHINE);
+    map.LoadFrom(dict, POLICY_LEVEL_MANDATORY, POLICY_SCOPE_MACHINE,
+                 POLICY_SOURCE_PLATFORM);
   }
 }
 
 }  // namespace policy