[RUM-8875] Add ability to manually add an activity to JankStats

Unity's main activity is started prior to initializing Datadog, so it misses adding the Activity to JankStats tracking. Add an internal method to allow manually adding an activity to JankStats tracking.

Author: fuzzybinary

features/dd-sdk-android-rum/api/apiSurface

@@ -160,6 +160,7 @@ class com.datadog.android.rum._RumInternalProxy
   fun updatePerformanceMetric(RumPerformanceMetric, Double)
   fun setInternalViewAttribute(String, Any?)
   fun setSyntheticsAttribute(String?, String?)
+  fun enableJankStatsTracking(android.app.Activity)
   companion object 
     fun setTelemetryConfigurationEventMapper(RumConfiguration.Builder, com.datadog.android.event.EventMapper<com.datadog.android.telemetry.model.TelemetryConfigurationEvent>): RumConfiguration.Builder
     fun setAdditionalConfiguration(RumConfiguration.Builder, Map<String, Any>): RumConfiguration.Builder

features/dd-sdk-android-rum/api/dd-sdk-android-rum.api

@@ -235,6 +235,7 @@ public final class com/datadog/android/rum/_RumInternalProxy {
 	public static final field Companion Lcom/datadog/android/rum/_RumInternalProxy$Companion;
 	public final fun addLongTask (JLjava/lang/String;)V
 	public final fun setInternalViewAttribute (Ljava/lang/String;Ljava/lang/Object;)V
+	public final fun enableJankStatsTracking (Landroid/app/Activity;)V
 	public final fun setSyntheticsAttribute (Ljava/lang/String;Ljava/lang/String;)V
 	public final fun updatePerformanceMetric (Lcom/datadog/android/rum/RumPerformanceMetric;D)V
 }

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/_RumInternalProxy.kt

@@ -6,6 +6,7 @@
 
 package com.datadog.android.rum
 
+import android.app.Activity
 import android.content.Intent
 import com.datadog.android.event.EventMapper
 import com.datadog.android.lint.InternalApi
@@ -60,6 +61,15 @@ class _RumInternalProxy internal constructor(private val rumMonitor: AdvancedRum
         rumMonitor.setSyntheticsAttribute(testId, resultId)
     }
 
+    /**
+     * Enables the tracking of JankStats for the given activity. This should only be necessary for the
+     * initial activity of an application if Datadog is initialized after that activity is created.
+     * @param activity the activity to track
+     */
+    fun enableJankStatsTracking(activity: Activity) {
+        rumMonitor.enableJankStatsTracking(activity)
+    }
+
     internal fun setSyntheticsAttributeFromIntent(intent: Intent) {
         @Suppress("TooGenericExceptionCaught")
         val extras = try { intent.extras } catch (_: Exception) { null }

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/RumFeature.kt

@@ -6,6 +6,7 @@
 
 package com.datadog.android.rum.internal
 
+import android.app.Activity
 import android.app.ActivityManager
 import android.app.Application
 import android.app.ApplicationExitInfo
@@ -379,6 +380,24 @@ internal class RumFeature(
         }
     }
 
+    /**
+     * Enables the tracking of JankStats for the given activity. This should only be necessary for the
+     * initial activity of an application if Datadog is initialized after that activity is created.
+     * @param activity the activity to track
+     */
+    internal fun enableJankStatsTracking(activity: Activity) {
+        try {
+            jankStatsActivityLifecycleListener?.onActivityStarted(activity)
+        } catch (@Suppress("TooGenericExceptionCaught") e: Exception) {
+            sdkCore.internalLogger.log(
+                InternalLogger.Level.ERROR,
+                InternalLogger.Target.TELEMETRY,
+                { FAILED_TO_ENABLE_JANK_STATS_TRACKING_MANUALLY },
+                e
+            )
+        }
+    }
+
     private fun registerTrackingStrategies(appContext: Context) {
         actionTrackingStrategy.register(sdkCore, appContext)
         viewTrackingStrategy.register(sdkCore, appContext)
@@ -619,6 +638,8 @@ internal class RumFeature(
         internal const val RUM_FEATURE_NOT_YET_INITIALIZED =
             "RUM feature is not initialized yet, you need to register it with a" +
                 " SDK instance by calling SdkCore#registerFeature method."
+        internal const val FAILED_TO_ENABLE_JANK_STATS_TRACKING_MANUALLY =
+            "Manually enabling JankStats tracking threw an exception."
 
         private fun provideUserTrackingStrategy(
             touchTargetExtraAttributesProviders: Array<ViewAttributesProvider>,

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/monitor/AdvancedRumMonitor.kt

@@ -6,6 +6,7 @@
 
 package com.datadog.android.rum.internal.monitor
 
+import android.app.Activity
 import com.datadog.android.core.feature.event.ThreadDump
 import com.datadog.android.internal.telemetry.InternalTelemetryEvent
 import com.datadog.android.rum.RumErrorSource
@@ -51,4 +52,6 @@ internal interface AdvancedRumMonitor : RumMonitor, AdvancedNetworkRumMonitor {
     fun setInternalViewAttribute(key: String, value: Any?)
 
     fun setSyntheticsAttribute(testId: String, resultId: String)
+
+    fun enableJankStatsTracking(activity: Activity)
 }

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/monitor/DatadogRumMonitor.kt

@@ -6,6 +6,7 @@
 
 package com.datadog.android.rum.internal.monitor
 
+import android.app.Activity
 import android.app.ActivityManager
 import android.os.Handler
 import com.datadog.android.api.InternalLogger
@@ -644,6 +645,16 @@ internal class DatadogRumMonitor(
         handleEvent(RumRawEvent.TelemetryEventWrapper(telemetryEvent))
     }
 
+    override fun enableJankStatsTracking(activity: Activity) {
+        val rumFeatureScope = sdkCore.getFeature(Feature.RUM_FEATURE_NAME)
+            ?.unwrap<RumFeature>()
+        if (rumFeatureScope == null) {
+            return
+        }
+
+        rumFeatureScope.enableJankStatsTracking(activity)
+    }
+
     // endregion
 
     // region Internal

features/dd-sdk-android-rum/src/main/kotlin/com/datadog/android/rum/internal/vitals/JankStatsActivityLifecycleListener.kt

@@ -165,6 +165,9 @@ internal class JankStatsActivityLifecycleListener(
 
     private fun trackActivity(window: Window, activity: Activity) {
         val list = activeActivities[window] ?: mutableListOf()
+        if (list.find { it.get() == activity } != null) {
+            return
+        }
         list.add(WeakReference(activity))
         activeActivities[window] = list
     }

features/dd-sdk-android-rum/src/test/kotlin/com/datadog/android/rum/RumInternalProxyTest.kt

@@ -6,6 +6,7 @@
 
 package com.datadog.android.rum
 
+import android.app.Activity
 import com.datadog.android.rum.internal.monitor.AdvancedRumMonitor
 import com.datadog.android.rum.utils.forge.Configurator
 import fr.xgouchet.elmyr.Forge
@@ -62,4 +63,18 @@ internal class RumInternalProxyTest {
         // Then
         verify(mockRumMonitor).updatePerformanceMetric(metric, value)
     }
+
+    @Test
+    fun `M proxy enableJankStatsTracking to RumMonitor W enableJankStatsTracking()`() {
+        // Given
+        val mockRumMonitor = mock(AdvancedRumMonitor::class.java)
+        val proxy = _RumInternalProxy(mockRumMonitor)
+        val activity: Activity = mock()
+
+        // When
+        proxy.enableJankStatsTracking(activity)
+
+        // Then
+        verify(mockRumMonitor).enableJankStatsTracking(activity)
+    }
 }

features/dd-sdk-android-rum/src/test/kotlin/com/datadog/android/rum/internal/RumFeatureTest.kt

@@ -6,6 +6,7 @@
 
 package com.datadog.android.rum.internal
 
+import android.app.Activity
 import android.app.ActivityManager
 import android.app.Application
 import android.app.ApplicationExitInfo
@@ -534,6 +535,25 @@ internal class RumFeatureTest {
             .isNull()
     }
 
+    @Test
+    fun `M call onActivityStarted W enableJankStatsTracking()`() {
+        // Given
+        val activity: Activity = mock()
+        testedFeature = RumFeature(
+            mockSdkCore,
+            fakeApplicationId.toString(),
+            fakeConfiguration,
+            lateCrashReporterFactory = { mockLateCrashReporter }
+        )
+        testedFeature.jankStatsActivityLifecycleListener = mock()
+
+        // When
+        testedFeature.enableJankStatsTracking(activity)
+
+        // Then
+        verify(testedFeature.jankStatsActivityLifecycleListener)!!.onActivityStarted(activity)
+    }
+
     @Test
     fun `M use noop viewTrackingStrategy W onStop()`() {
         // Given

features/dd-sdk-android-rum/src/test/kotlin/com/datadog/android/rum/internal/monitor/DatadogRumMonitorTest.kt

@@ -6,6 +6,7 @@
 
 package com.datadog.android.rum.internal.monitor
 
+import android.app.Activity
 import android.app.ActivityManager
 import android.os.Handler
 import com.datadog.android.api.InternalLogger
@@ -1911,6 +1912,22 @@ internal class DatadogRumMonitorTest {
         }
     }
 
+    @Test
+    fun `M call enableJankStatsTracking on RUM feature W enableJankStatsTracking`() {
+        // Given
+        val mockActivity = mock<Activity>()
+        val mockRumScope = mock<FeatureScope>()
+        whenever(mockSdkCore.getFeature(Feature.RUM_FEATURE_NAME)) doReturn mockRumScope
+        val mockRumFeature = mock<RumFeature>()
+        whenever(mockRumScope.unwrap<RumFeature>()) doReturn mockRumFeature
+
+        // When
+        testedMonitor.enableJankStatsTracking(mockActivity)
+
+        // Then
+        verify(mockRumFeature).enableJankStatsTracking(mockActivity)
+    }
+
     @Test
     fun `M call sessionEndedMetricDispatcher W addSkippedFrame`(
         @IntForgery(min = 0, max = 100) count: Int,