[Cast MRP] Add metrics for app availability success/failure.

This should match the metric that is currently recorded in the
extension.

Bug: 698940
Change-Id: I2c1310a9b0911f4d610dfd5d8c74714ff8132913
Reviewed-on: https://chromium-review.googlesource.com/944719Reviewed-by: mark a. foltz <mfoltz@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Commit-Queue: Derek Cheng <imcheng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541994}

chrome/browser/media/router/BUILD.gn

@@ -93,6 +93,8 @@ static_library("router") {
       "providers/cast/cast_app_discovery_service.h",
       "providers/cast/cast_media_route_provider.cc",
       "providers/cast/cast_media_route_provider.h",
+      "providers/cast/cast_media_route_provider_metrics.cc",
+      "providers/cast/cast_media_route_provider_metrics.h",
       "providers/cast/chrome_cast_message_handler.cc",
       "providers/cast/chrome_cast_message_handler.h",
       "providers/cast/dual_media_sink_service.cc",

chrome/browser/media/router/providers/cast/cast_app_discovery_service.cc

@@ -4,6 +4,7 @@
 
 #include "chrome/browser/media/router/providers/cast/cast_app_discovery_service.h"
 
+#include "chrome/browser/media/router/providers/cast/cast_media_route_provider_metrics.h"
 #include "components/cast_channel/cast_message_handler.h"
 #include "components/cast_channel/cast_socket.h"
 #include "components/cast_channel/cast_socket_service.h"
@@ -109,14 +110,17 @@ void CastAppDiscoveryService::RequestAppAvailability(
   message_handler_->RequestAppAvailability(
       socket, app_id,
       base::BindOnce(&CastAppDiscoveryService::UpdateAppAvailability,
-                     weak_ptr_factory_.GetWeakPtr(), sink_id));
+                     weak_ptr_factory_.GetWeakPtr(), base::TimeTicks::Now(),
+                     sink_id));
 }
 
 void CastAppDiscoveryService::UpdateAppAvailability(
+    base::TimeTicks start_time,
     const MediaSink::Id& sink_id,
     const std::string& app_id,
     cast_channel::GetAppAvailabilityResult result) {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+  RecordAppAvailabilityResult(result, base::TimeTicks::Now() - start_time);
   if (!base::ContainsKey(sinks_, sink_id))
     return;
 

chrome/browser/media/router/providers/cast/cast_app_discovery_service.h

@@ -15,6 +15,7 @@
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/sequenced_task_runner.h"
+#include "base/time/time.h"
 #include "chrome/browser/media/router/discovery/mdns/cast_media_sink_service_impl.h"
 #include "chrome/browser/media/router/providers/cast/cast_app_availability_tracker.h"
 #include "chrome/common/media_router/media_sink.h"
@@ -68,7 +69,10 @@ class CastAppDiscoveryService : public CastMediaSinkServiceImpl::Observer {
 
   // Updates the availability result for |sink_id| and |app_id| with |result|,
   // and notifies callbacks with updated sink query results.
-  void UpdateAppAvailability(const MediaSink::Id& sink_id,
+  // |start_time| is the time when the app availability request was made, and
+  // is used for metrics.
+  void UpdateAppAvailability(base::TimeTicks start_time,
+                             const MediaSink::Id& sink_id,
                              const std::string& app_id,
                              cast_channel::GetAppAvailabilityResult result);
 

chrome/browser/media/router/providers/cast/cast_media_route_provider_metrics.cc

+// Copyright 2018 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/media/router/providers/cast/cast_media_route_provider_metrics.h"
+
+#include "base/metrics/histogram_macros.h"
+#include "base/time/time.h"
+
+namespace media_router {
+
+void RecordAppAvailabilityResult(cast_channel::GetAppAvailabilityResult result,
+                                 base::TimeDelta duration) {
+  if (result == cast_channel::GetAppAvailabilityResult::kUnknown)
+    UMA_HISTOGRAM_TIMES(kHistogramAppAvailabilityFailure, duration);
+  else
+    UMA_HISTOGRAM_TIMES(kHistogramAppAvailabilitySuccess, duration);
+}
+
+}  // namespace media_router

chrome/browser/media/router/providers/cast/cast_media_route_provider_metrics.h

+// Copyright 2018 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.
+
+#ifndef CHROME_BROWSER_MEDIA_ROUTER_PROVIDERS_CAST_CAST_MEDIA_ROUTE_PROVIDER_METRICS_H_
+#define CHROME_BROWSER_MEDIA_ROUTER_PROVIDERS_CAST_CAST_MEDIA_ROUTE_PROVIDER_METRICS_H_
+
+#include "base/time/time.h"
+#include "components/cast_channel/cast_message_util.h"
+
+namespace media_router {
+
+// Histogram names for app availability.
+static constexpr char kHistogramAppAvailabilitySuccess[] =
+    "MediaRouter.Cast.App.Availability.Success";
+static constexpr char kHistogramAppAvailabilityFailure[] =
+    "MediaRouter.Cast.App.Availability.Failure";
+
+// Records the result of an app availability request and how long it took.
+// If |result| is kUnknown, then a failure is recorded. Otherwise, a success
+// is recorded.
+void RecordAppAvailabilityResult(cast_channel::GetAppAvailabilityResult result,
+                                 base::TimeDelta duration);
+
+}  // namespace media_router
+
+#endif  // CHROME_BROWSER_MEDIA_ROUTER_PROVIDERS_CAST_CAST_MEDIA_ROUTE_PROVIDER_METRICS_H_

chrome/browser/media/router/providers/cast/cast_media_route_provider_metrics_unittest.cc

+// Copyright 2018 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/media/router/providers/cast/cast_media_route_provider_metrics.h"
+#include "base/test/histogram_tester.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using base::Bucket;
+using testing::ElementsAre;
+
+namespace media_router {
+
+TEST(CastMediaRouteProviderMetricsTest, RecordAppAvailabilityResult) {
+  base::HistogramTester tester;
+
+  RecordAppAvailabilityResult(
+      cast_channel::GetAppAvailabilityResult::kAvailable,
+      base::TimeDelta::FromMilliseconds(111));
+  RecordAppAvailabilityResult(
+      cast_channel::GetAppAvailabilityResult::kUnavailable,
+      base::TimeDelta::FromMilliseconds(222));
+  tester.ExpectTimeBucketCount(kHistogramAppAvailabilitySuccess,
+                               base::TimeDelta::FromMilliseconds(111), 1);
+  tester.ExpectTimeBucketCount(kHistogramAppAvailabilitySuccess,
+                               base::TimeDelta::FromMilliseconds(222), 1);
+
+  RecordAppAvailabilityResult(cast_channel::GetAppAvailabilityResult::kUnknown,
+                              base::TimeDelta::FromMilliseconds(333));
+  tester.ExpectTimeBucketCount(kHistogramAppAvailabilityFailure,
+                               base::TimeDelta::FromMilliseconds(333), 1);
+}
+
+}  // namespace media_router

chrome/test/BUILD.gn

@@ -3065,6 +3065,7 @@ test("unit_tests") {
       "../browser/media/router/mojo/media_sink_service_status_unittest.cc",
       "../browser/media/router/providers/cast/cast_app_availability_tracker_unittest.cc",
       "../browser/media/router/providers/cast/cast_app_discovery_service_unittest.cc",
+      "../browser/media/router/providers/cast/cast_media_route_provider_metrics_unittest.cc",
       "../browser/media/router/providers/cast/dual_media_sink_service_unittest.cc",
       "../browser/media/router/providers/extension/extension_media_route_provider_proxy_unittest.cc",
       "../browser/media/router/providers/wired_display/wired_display_media_route_provider_unittest.cc",

tools/metrics/histograms/histograms.xml

@@ -37654,6 +37654,16 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <summary>Various usage counts for media galleries.</summary>
 </histogram>
 
+<histogram base="true" name="MediaRouter.Cast.App.Availability" units="ms">
+<!-- Name completed by histogram_suffixes name="MediaRouterSuccess" -->
+
+  <owner>imcheng@chromium.org</owner>
+  <summary>
+    Round trip time for a Cast app availability request. Can be suffixed with
+    Success or Failure.
+  </summary>
+</histogram>
+
 <histogram name="MediaRouter.Cast.Channel.ConnectResult" enum="BooleanSuccess">
   <owner>zhaobin@chromium.org</owner>
   <summary>
@@ -107819,6 +107829,12 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <affected-histogram name="Media.RebuffersCount"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="MediaRouterSuccess" separator=".">
+  <suffix name="Failure" label="Failure"/>
+  <suffix name="Success" label="Success"/>
+  <affected-histogram name="MediaRouter.Cast.App.Availability"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="MediaTimelineWidths" separator=".">
   <suffix name="32_47"/>
   <suffix name="48_79"/>