feat: Propagate traceId to the Android SDK

package-dev/Runtime/SentryInitialization.cs

@@ -86,6 +86,10 @@ public static void Init()
 
                 SentryUnity.Init(options);
 
+#if SENTRY_NATIVE_ANDROID
+                SentryNativeAndroid.SetTraceId(options);
+#endif
+
 #if !SENTRY_WEBGL
                 if (options.TracesSampleRate > 0.0f && options.AutoStartupTraces)
                 {

src/Sentry.Unity.Android/SentryJava.cs

@@ -13,6 +13,7 @@ internal interface ISentryJava
     public string? GetInstallationId(IJniExecutor jniExecutor);
     public bool? CrashedLastRun(IJniExecutor jniExecutor);
     public void Close(IJniExecutor jniExecutor);
+    public void ContinueTrace(IJniExecutor jniExecutor, string traceId);
     public void WriteScope(
         IJniExecutor jniExecutor,
         int? GpuId,
@@ -170,6 +171,15 @@ public void Close(IJniExecutor jniExecutor)
         });
     }
 
+    public void ContinueTrace(IJniExecutor jniExecutor, string traceId)
+    {
+        jniExecutor.Run(() =>
+        {
+            using var sentry = GetSentryJava();
+            sentry.CallStatic<AndroidJavaObject>("continueTrace", traceId, null);
+        });
+    }
+
     public void WriteScope(
         IJniExecutor jniExecutor,
         int? GpuId,

src/Sentry.Unity.Android/SentryNativeAndroid.cs

@@ -132,6 +132,24 @@ public static void Configure(SentryUnityOptions options, ISentryUnityInfo sentry
         options.DiagnosticLogger?.LogInfo("Successfully configured the Android SDK");
     }
 
+    public static void SetTraceId(SentryUnityOptions options)
+    {
+        options.DiagnosticLogger?.LogInfo("Setting Trace ID");
+
+        var traceId = SentrySdk.GetTraceHeader()?.TraceId;
+        if (traceId is null)
+        {
+            options.DiagnosticLogger?.LogInfo("fucking trace id is null");
+        }
+        else
+        {
+            options.DiagnosticLogger?.LogInfo("Setting the trace ID on the native layer {0}", traceId);
+
+            JniExecutor ??= new JniExecutor(options.DiagnosticLogger);
+            SentryJava.ContinueTrace(JniExecutor, traceId.ToString());
+        }
+    }
+
     /// <summary>
     /// Closes the native Android support.
     /// </summary>

test/Sentry.Unity.Android.Tests/TestSentryJava.cs

@@ -19,6 +19,7 @@ public void Init(IJniExecutor jniExecutor, SentryUnityOptions options, TimeSpan
     public bool? CrashedLastRun(IJniExecutor jniExecutor) => IsCrashedLastRun;
 
     public void Close(IJniExecutor jniExecutor) { }
+    public void ContinueTrace(IJniExecutor jniExecutor, string traceId) { }
 
     public void WriteScope(
         IJniExecutor jniExecutor,