[iOS] Add active and inactive tabs count startup metrics

Log the number of inactive tabs by arm definition and the number of
absolute inactive tab (older than 21 days) and the number of active tab
by arm definition.

Fixed: 1440123
Change-Id: I6c782535e22af450d366e8b422a736c26b2f8a01
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4459611
Reviewed-by: Olivier Robin <olivierrobin@chromium.org>
Commit-Queue: Aliona Dangla <alionadangla@chromium.org>
Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Reviewed-by: Louis Romero <lpromero@google.com>
Reviewed-by: Dana Fried <dfried@chromium.org>
Code-Coverage: Findit <findit-for-me@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#1135950}

ios/chrome/app/application_delegate/metrics_mediator.mm

@@ -312,6 +312,14 @@ - (void)setAppGroupMetricsEnabled:(BOOL)enabled;
 - (void)updateMetricsPrefsOnPermissionChange:(BOOL)enabled;
 // Logs the inactive tabs settings preference.
 + (void)recordInactiveTabsSettingsAtStartup:(int)preference;
+// Logs the number of active tabs (based on the arm's definition of
+// active/inactive).
++ (void)recordNumActiveTabAtStartup:(int)numTabs;
+// Logs the number of inactive tabs (based on the arm's definition of
+// active/inactive).
++ (void)recordNumInactiveTabAtStartup:(int)numTabs;
+// Logs the number of tabs older than 21 days.
++ (void)recordNumAbsoluteInactiveTabAtStartup:(int)numTabs;
 // Logs the number of tabs with UMAHistogramCount100 and allows testing.
 + (void)recordNumTabAtStartup:(int)numTabs;
 // Logs the number of tabs with UMAHistogramCount100 and allows testing.
@@ -406,6 +414,15 @@ + (void)logLaunchMetricsWithStartupInformation:
   int numLiveNTPTabs = 0;
   int numOldTabs = 0;
   int numDuplicatedTabs = 0;
+  int numActiveTabs = 0;
+  int numInactiveTabs = 0;
+  int numAbsoluteInactiveTabs = 0;
+
+  // Amount of time after which a tab is considered as old.
+  constexpr base::TimeDelta kOldTabThreshold = base::Days(7);
+
+  // Amount of time after which a tab is considered as absolutely inactive.
+  constexpr base::TimeDelta kAbsoluteInactiveTabThreshold = base::Days(21);
 
   NSMutableSet* uniqueURLs = [NSMutableSet set];
   std::vector<base::TimeDelta> timesSinceCreation;
@@ -429,6 +446,8 @@ + (void)logLaunchMetricsWithStartupInformation:
     const int inactiveWebStateListCount = inactiveWebStateList->count();
 
     numTabs += webStateListCount + inactiveWebStateListCount;
+    numActiveTabs += webStateListCount;
+    numInactiveTabs += inactiveWebStateListCount;
     // All inactive tabs are inactive since minimum 7 days or more.
     numOldTabs += inactiveWebStateListCount;
 
@@ -450,9 +469,14 @@ + (void)logLaunchMetricsWithStartupInformation:
         [uniqueURLs addObject:URLString];
       }
 
-      // Count old (e.g. more than 7 days inactive) tabs.
-      if (now - webState->GetLastActiveTime() > base::Days(7)) {
+      // Count old tabs.
+      base::TimeDelta inactiveTime = now - webState->GetLastActiveTime();
+      if (inactiveTime > kOldTabThreshold) {
         numOldTabs++;
+        // Count absolute inactive tabs.
+        if (inactiveTime > kAbsoluteInactiveTabThreshold) {
+          numAbsoluteInactiveTabs++;
+        }
       }
 
       // Calculate the age (time elapsed since creation) of WebState.
@@ -468,13 +492,23 @@ + (void)logLaunchMetricsWithStartupInformation:
       // Calculate the age (time elapsed since creation) of WebState.
       base::TimeDelta timeSinceCreation = now - webState->GetCreationTime();
       timesSinceCreation.push_back(timeSinceCreation);
+
+      // Calculate absolute inactive tabs.
+      base::TimeDelta inactiveTime =
+          base::Time::Now() - webState->GetLastActiveTime();
+      if (inactiveTime > kAbsoluteInactiveTabThreshold) {
+        numAbsoluteInactiveTabs++;
+      }
     }
   }
 
   if (startupInformation.isColdStart) {
     [self recordInactiveTabsSettingsAtStartup:
               GetApplicationContext()->GetLocalState()->GetInteger(
                   prefs::kInactiveTabsTimeThreshold)];
+    [self recordNumActiveTabAtStartup:numActiveTabs];
+    [self recordInactiveTabsSettingsAtStartup:numInactiveTabs];
+    [self recordNumAbsoluteInactiveTabAtStartup:numAbsoluteInactiveTabs];
     [self recordNumTabAtStartup:numTabs];
     [self recordNumNTPTabAtStartup:numNTPTabs];
     [self recordNumOldTabAtStartup:numOldTabs];
@@ -688,6 +722,18 @@ + (void)recordInactiveTabsSettingsAtStartup:(int)preference {
                             InactiveTabsSettingFromPreference(preference));
 }
 
++ (void)recordNumActiveTabAtStartup:(int)numTabs {
+  base::UmaHistogramCounts100("Tabs.ActiveCountAtStartup", numTabs);
+}
+
++ (void)recordNumInactiveTabAtStartup:(int)numTabs {
+  base::UmaHistogramCounts100("Tabs.InactiveCountAtStartup", numTabs);
+}
+
++ (void)recordNumAbsoluteInactiveTabAtStartup:(int)numTabs {
+  base::UmaHistogramCounts100("Tabs.OldCountAtStartup", numTabs);
+}
+
 + (void)recordNumTabAtStartup:(int)numTabs {
   base::UmaHistogramCounts100("Tabs.CountAtStartup", numTabs);
 }

tools/metrics/histograms/metadata/tab/histograms.xml

@@ -1061,6 +1061,17 @@ chromium-metrics-reviews@google.com.
   </token>
 </histogram>
 
+<histogram name="Tabs.ActiveCountAtStartup" units="tabs"
+    expires_after="2023-10-01">
+  <owner>alionadangla@chromium.org</owner>
+  <owner>lpromero@chromium.org</owner>
+  <owner>chromeleon@google.com</owner>
+  <summary>
+    [iOS] Records the number of tabs that are considered active as per the
+    current tab inactivity threshold. This is recorded at cold launch.
+  </summary>
+</histogram>
+
 <histogram name="Tabs.CountAtResume" units="tabs" expires_after="2024-01-15">
 <!-- This histogram was expired between 2022-11-02 and M111 -->
 
@@ -1113,6 +1124,17 @@ chromium-metrics-reviews@google.com.
   </summary>
 </histogram>
 
+<histogram name="Tabs.InactiveCountAtStartup" units="tabs"
+    expires_after="2023-10-01">
+  <owner>alionadangla@chromium.org</owner>
+  <owner>lpromero@chromium.org</owner>
+  <owner>chromeleon@google.com</owner>
+  <summary>
+    [iOS] Records the number of tabs that are considered inactive as per the
+    current tab inactivity threshold. This is recorded at cold launch.
+  </summary>
+</histogram>
+
 <histogram name="Tabs.LiveNTPCountAtResume" units="tabs"
     expires_after="2024-02-26">
   <owner>thegreenfrog@chromium.org</owner>
@@ -1221,6 +1243,16 @@ chromium-metrics-reviews@google.com.
   <token key="BatteryState" variants="BatteryState"/>
 </histogram>
 
+<histogram name="Tabs.OldCountAtStartup" units="tabs"
+    expires_after="2023-10-01">
+  <owner>alionadangla@chromium.org</owner>
+  <owner>lpromero@chromium.org</owner>
+  <owner>chromeleon@google.com</owner>
+  <summary>
+    [iOS] Number of tabs older than 21 days. Recorded at cold launch.
+  </summary>
+</histogram>
+
 <histogram name="Tabs.PersistedTabData.Critical.Map.Success"
     enum="BooleanSuccess" expires_after="2024-01-08">
   <owner>davidjm@chromium.org</owner>