Refresh policies from DM server periodically

chrome/browser/policy/device_management_policy_cache.h

Index: chrome/browser/policy/device_management_policy_cache.h
diff --git a/chrome/browser/policy/device_management_policy_cache.h b/chrome/browser/policy/device_management_policy_cache.h
index 5136059a8306c62fd3560b71d9a71603e4f5f32e..ffe63d4e65b0f50eeacdb8429c57436b675e7f60 100644
--- a/chrome/browser/policy/device_management_policy_cache.h
+++ b/chrome/browser/policy/device_management_policy_cache.h
@@ -33,8 +33,9 @@ class DeviceManagementPolicyCache {
   // cache files are ignored.
   void LoadPolicyFromFile();
 
-  // Resets the policy information.
-  void SetPolicy(const em::DevicePolicyResponse& policy);
+  // Resets the policy information. Returns true if the new policy is different
+  // from the previously stored policy.
+  bool SetPolicy(const em::DevicePolicyResponse& policy);
 
   // Gets the policy information. Ownership of the return value is transferred
   // to the caller.