Add DeviceADPolicyManager to provide AD policy.

chrome/browser/chromeos/settings/install_attributes.cc

Index: chrome/browser/chromeos/settings/install_attributes.cc
diff --git a/chrome/browser/chromeos/settings/install_attributes.cc b/chrome/browser/chromeos/settings/install_attributes.cc
index 50eb6581119fbda4f044f0a1301bfafdab15fed0..930c366228504050ad8f11a9310891271d32a07e 100644
--- a/chrome/browser/chromeos/settings/install_attributes.cc
+++ b/chrome/browser/chromeos/settings/install_attributes.cc
@@ -325,6 +325,13 @@ bool InstallAttributes::IsEnterpriseDevice() const {
       registration_mode_ == policy::DEVICE_MODE_ENTERPRISE_AD;
 }
 
+bool InstallAttributes::IsEnterpriseAD() const {
+  if (!device_locked_) {
+    return false;
+  }
+  return registration_mode_ == policy::DEVICE_MODE_ENTERPRISE_AD;
+}
+
 bool InstallAttributes::IsConsumerKioskDeviceWithAutoLaunch() {
   return device_locked_ &&
          registration_mode_ == policy::DEVICE_MODE_CONSUMER_KIOSK_AUTOLAUNCH;