arc: add api to record arc dns resolution failure

Second highest reason for checkin failure is due to failed dns query.
We're adding a metric to track how common this issue is for hostname
used by checkin apis and every other hostname.

Android change: http://ag/15364401

BUG=b:183412745
TEST=blocked android.googleapis.com in dns sink and verified that the
metric is reported in chrome://histograms

Change-Id: Ib7aa74d83624a02f4e675e26c14431d83441337f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3046942
Commit-Queue: Muhammad Hasan Khan <mhasank@chromium.org>
Reviewed-by: Yuichiro Hanada <yhanada@chromium.org>
Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Reviewed-by: Alex Gough <ajgo@chromium.org>
Reviewed-by: Hugo Benichi <hugobenichi@google.com>
Cr-Commit-Position: refs/heads/master@{#905370}

components/arc/metrics/arc_metrics_service.cc

@@ -119,6 +119,17 @@ const char* LowLatencyStylusLibraryTypeToString(
   return "";
 }
 
+const char* DnsQueryToString(mojom::ArcDnsQuery query) {
+  switch (query) {
+    case mojom::ArcDnsQuery::OTHER_HOST_NAME:
+      return "Other";
+    case mojom::ArcDnsQuery::ANDROID_API_HOST_NAME:
+      return "AndroidApi";
+  }
+  NOTREACHED();
+  return "";
+}
+
 }  // namespace
 
 // static
@@ -356,6 +367,15 @@ void ArcMetricsService::ReportAppKill(mojom::AppKillPtr app_kill) {
   }
 }
 
+void ArcMetricsService::ReportDnsQueryResult(mojom::ArcDnsQuery query,
+                                             bool success) {
+  DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
+  std::string metric_name =
+      base::StrCat({"Arc.Net.DnsQuery.", DnsQueryToString(query)});
+  VLOG(1) << metric_name << ": " << success;
+  base::UmaHistogramBoolean(metric_name, success);
+}
+
 void ArcMetricsService::NotifyLowMemoryKill() {
   for (auto& obs : app_kill_observers_)
     obs.OnArcLowMemoryKill();

components/arc/metrics/arc_metrics_service.h

@@ -102,6 +102,7 @@ class ArcMetricsService : public KeyedService,
                           mojom::BootType boot_type) override;
   void ReportNativeBridge(mojom::NativeBridgeType native_bridge_type) override;
   void ReportCompanionLibApiUsage(mojom::CompanionLibApiId api_id) override;
+  void ReportDnsQueryResult(mojom::ArcDnsQuery query, bool success) override;
   void ReportAppKill(mojom::AppKillPtr app_kill) override;
   void ReportArcCorePriAbiMigEvent(
       mojom::ArcCorePriAbiMigEvent event_type) override;

components/arc/mojom/metrics.mojom

@@ -1,7 +1,7 @@
 // Copyright 2016 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.
-// Next MinVersion: 13
+// Next MinVersion: 14
 
 module arc.mojom;
 
@@ -149,6 +149,15 @@ enum CompanionLibApiId {
   IS_CLIPPING_TO_TASK_DISABLED = 23,
 };
 
+[Extensible]
+enum ArcDnsQuery {
+  // All other hostnames.
+  OTHER_HOST_NAME = 0,
+
+  // android.googleapis.com used by Android checkin.
+  ANDROID_API_HOST_NAME = 1,
+};
+
 // Describes the type of app kill being reported.
 [Extensible]
 enum AppKillType {
@@ -232,7 +241,7 @@ enum LowLatencyStylusLibApiId {
   kGLInkOverlaySetViewMatrix = 4,
 };
 
-// Next method ID: 16
+// Next method ID: 17
 interface MetricsHost {
   // Reports boot progress events from ARC instance.
   ReportBootProgress@0(array<BootProgressEvent> events,
@@ -293,6 +302,11 @@ interface MetricsHost {
   [MinVersion=12] ReportPerAppFixupMetrics@15(
       mojo_base.mojom.TimeDelta duration,
       uint32 number_of_directories);
+
+  // Reports the result of DNS query inside ARC.
+  [MinVersion=13] ReportDnsQueryResult@16(
+      ArcDnsQuery query,
+      bool success);
 };
 
 // Next method ID: 3

tools/metrics/histograms/histograms_xml/arc/histograms.xml

@@ -959,6 +959,24 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
   </summary>
 </histogram>
 
+<histogram name="Arc.Net.DnsQuery.AndroidApi" enum="BooleanSuccess"
+    expires_after="2022-07-22">
+  <owner>mhasank@google.com</owner>
+  <owner>arc-core@google.com</owner>
+  <summary>
+    Records the success result of DNS query resolution inside ARC.
+  </summary>
+</histogram>
+
+<histogram name="Arc.Net.DnsQuery.Other" enum="BooleanSuccess"
+    expires_after="2022-07-22">
+  <owner>mhasank@google.com</owner>
+  <owner>arc-core@google.com</owner>
+  <summary>
+    Records the success result of DNS query resolution inside ARC.
+  </summary>
+</histogram>
+
 <histogram name="Arc.OOMKills.Count" units="kills" expires_after="2021-03-07">
   <obsolete>
     Removed in Oct 2020. Now reported as Memory.OOMKills.Count.