Refactor: Inject StatisticsProvider as a dependency of DeviceCloudPolicyInitializer.

chrome/browser/chromeos/policy/enrollment_handler_chromeos.cc

 // Copyright (c) 2012 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 "chrome/browser/chromeos/policy/enrollment_handler_chromeos.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/location.h"
@@ skipping 100 matching lines @@
 }
 
 EnrollmentHandlerChromeOS::~EnrollmentHandlerChromeOS() {
   Stop();
   store_->RemoveObserver(this);
 }
 
 void EnrollmentHandlerChromeOS::StartEnrollment() {
   CHECK_EQ(STEP_PENDING, enrollment_step_);
   enrollment_step_ = STEP_STATE_KEYS;
+
+  if (client_->machine_id().empty()) {
+    LOG(ERROR) << "Machine id empty.";
+    ReportResult(EnrollmentStatus::ForStatus(
+        EnrollmentStatus::STATUS_NO_MACHINE_IDENTIFICATION));
+    return;
+  }
+  if (client_->machine_model().empty()) {
+    LOG(ERROR) << "Machine model empty.";
+    ReportResult(EnrollmentStatus::ForStatus(
+        EnrollmentStatus::STATUS_NO_MACHINE_IDENTIFICATION));
+    return;
+  }

[Mattias Nissler (ping if slow), 2016/09/29 09:12:26]

Since device policy is the only case where machine id and machine model are
supposed to be configured, it seems a bit backwards to use CloudPolicyClient as
the vehicle to carry them around now.

Maybe a cleaner approach would be to just remove them from the constructor of
CloudPolicyClient and pass them to CloudPolicyClient::Register() as parameters?
I think that would clear up the data flow. While you're doing this, you probably
also want to get rid of the submit_machine_id_ thing (this was put in to recover
devices in the field from an earlier bug, but is no longer needed AFAIK).

+
   state_keys_broker_->RequestStateKeys(
       base::Bind(&EnrollmentHandlerChromeOS::HandleStateKeysResult,
                  weak_ptr_factory_.GetWeakPtr()));
 }
 
 std::unique_ptr<CloudPolicyClient> EnrollmentHandlerChromeOS::ReleaseClient() {
   Stop();
   return std::move(client_);
 }
 
@@ skipping 359 matching lines @@
                  << ", validation: " << status.validation_status()
                  << ", store: " << status.store_status()
                  << ", lock: " << status.lock_status();
   }
 
   if (!callback.is_null())
     callback.Run(status);
 }
 
 }  // namespace policy