Expose signing key from cloud policy stores

chrome/browser/chromeos/policy/device_cloud_policy_store_chromeos.cc

Index: chrome/browser/chromeos/policy/device_cloud_policy_store_chromeos.cc
diff --git a/chrome/browser/chromeos/policy/device_cloud_policy_store_chromeos.cc b/chrome/browser/chromeos/policy/device_cloud_policy_store_chromeos.cc
index b3bfde5f21bf78f3fa2c780e86239b174fc0ab6d..3fc16b0e838bbf1ffcb84ff929364b32126825fa 100644
--- a/chrome/browser/chromeos/policy/device_cloud_policy_store_chromeos.cc
+++ b/chrome/browser/chromeos/policy/device_cloud_policy_store_chromeos.cc
@@ -198,6 +198,14 @@ void DeviceCloudPolicyStoreChromeOS::UpdateFromService() {
       }
       policy_map_.Swap(&new_policy_map);
 
+      DCHECK(owning_domain_.empty() ||
+             owning_domain_ == install_attributes_->GetDomain());
+      owning_domain_ = install_attributes_->GetDomain();
+
+      scoped_refptr<ownership::PublicKey> key =
+          device_settings_service_->GetPublicKey();
+      public_key_ = key ? key->as_string() : std::string();
+
       NotifyStoreLoaded();
       return;
     }