Use the Windows MDM API to check if the machine is being managed.

components/update_client/updater_state.cc

Index: components/update_client/updater_state.cc
diff --git a/components/update_client/updater_state.cc b/components/update_client/updater_state.cc
index 035e6c2f2302ec3e78fc02b1737488c6b81017da..3f531fc77a0401c3a5eb7cdb8da6f66c2f8b5aee 100644
--- a/components/update_client/updater_state.cc
+++ b/components/update_client/updater_state.cc
@@ -15,7 +15,7 @@
 
 namespace update_client {
 
-const char UpdaterState::kDomainJoined[] = "domainjoined";
+const char UpdaterState::kIsEnterpriseManaged[] = "domainjoined";

[grt (UTC plus 2), 2017/02/10 12:12:26]

nit: please drop a comment here explaining why the name and value don't match so
that someone like me doesn't come along and change the value 6 months from now.
:-)

[Roger Tawa OOO till Jul 10th, 2017/02/13 20:30:06]

I'm currently discussing with omaha folks and I may just change it here right
away.  If not I'll add the comment.

 
 UpdaterState::UpdaterState(bool is_machine) : is_machine_(is_machine) {}
 
@@ -34,7 +34,7 @@ std::unique_ptr<UpdaterState::Attributes> UpdaterState::GetState(
 
 #if defined(OS_WIN)
 void UpdaterState::ReadState() {
-  is_joined_to_domain_ = IsJoinedToDomain();
+  is_enterprise_managed_ = IsEnterpriseManaged();
 
 #if defined(GOOGLE_CHROME_BUILD)
   updater_name_ = GetUpdaterName();
@@ -50,7 +50,7 @@ void UpdaterState::ReadState() {
 UpdaterState::Attributes UpdaterState::BuildAttributes() const {
   Attributes attributes;
 
-  attributes[kDomainJoined] = is_joined_to_domain_ ? "1" : "0";
+  attributes[kIsEnterpriseManaged] = is_enterprise_managed_ ? "1" : "0";
 
   attributes["name"] = updater_name_;