Added metric for policy "device_id" field validity.

This metric extend cl/2047063. This allow to collect the same metrics
when policies are load from disk.

Bug: 653849
Change-Id: I044c8236be37d28ea43c94c508088faa7e5b6d64
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2422785
Commit-Queue: Martin Rodriguez <rodmartin@google.com>
Reviewed-by: Maksim Ivanov <emaxx@chromium.org>
Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811724}

chrome/browser/chromeos/policy/device_cloud_policy_store_chromeos.cc

@@ -206,9 +206,14 @@ void DeviceCloudPolicyStoreChromeOS::UpdateFromService() {
   if (service_status == chromeos::DeviceSettingsService::STORE_SUCCESS) {
     policy_ = std::make_unique<em::PolicyData>();
     const em::PolicyData* policy_data = device_settings_service_->policy_data();
-    if (policy_data)
+    if (policy_data) {
       policy_->MergeFrom(*policy_data);
 
+      RecordDeviceIdValidityMetric(
+          "Enterprise.CachedDevicePolicyDeviceIdValidity", *policy_data,
+          *install_attributes_);
+    }
+
     PolicyMap new_policy_map;
     if (is_managed()) {
       DecodeDevicePolicy(*device_settings_service_->device_settings(),

tools/metrics/histograms/histograms_xml/enterprise/histograms.xml

@@ -170,6 +170,18 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   <summary>URL fetcher status for auto-enrollment requests.</summary>
 </histogram>
 
+<histogram base="true" name="Enterprise.CachedDevicePolicyDeviceIdValidity"
+    enum="EnterprisePolicyDeviceIdValidity" expires_after="M95">
+  <owner>emaxx@chromium.org</owner>
+  <owner>rodmartin@chromium.org</owner>
+  <summary>
+    Result of the device ID validation in the device policy blob for those which
+    were loaded from disk. This validation happens on enrolled devices on
+    startup, on scheduled policy reloads that happen every few hours, and on
+    forced policy reloads.
+  </summary>
+</histogram>
+
 <histogram name="Enterprise.CBCMPolicyInvalidations"
     enum="EnterprisePolicyInvalidations" expires_after="2021-06-16">
   <owner>anthonyvd@google.com</owner>