Refactor usage of ProcessName in Fireperf. (#6963)

- This is based on
`firebase-sessions/src/main/kotlin/com/google/firebase/sessions/ProcessDetailsProvider.kt`
- Usage in `AppStartTrace` and `TransportManager`
- Reverts changes in `firebase-sessions/src/main/` to `main`

Author: tejasd

firebase-perf/src/main/java/com/google/firebase/perf/metrics/AppStartTrace.java

@@ -14,6 +14,8 @@
 
 package com.google.firebase.perf.metrics;
 
+import static com.google.firebase.perf.util.AppProcessesProvider.getAppProcesses;
+
 import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.app.ActivityManager;
@@ -509,17 +511,10 @@ public static boolean isAnyAppProcessInForeground(Context appContext) {
     if (activityManager == null) {
       return true;
     }
-    List<ActivityManager.RunningAppProcessInfo> appProcesses =
-        activityManager.getRunningAppProcesses();
-    if (appProcesses != null) {
-      String appProcessName = appContext.getPackageName();
-      String allowedAppProcessNamePrefix = appProcessName + ":";
+    List<ActivityManager.RunningAppProcessInfo> appProcesses = getAppProcesses(appContext);
+    if (!appProcesses.isEmpty()) {
       for (ActivityManager.RunningAppProcessInfo appProcess : appProcesses) {
-        if (appProcess.importance != ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
-          continue;
-        }
-        if (appProcess.processName.equals(appProcessName)
-            || appProcess.processName.startsWith(allowedAppProcessNamePrefix)) {
+        if (appProcess.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
           boolean isAppInForeground = true;
 
           // For the case when the app is in foreground and the device transitions to sleep mode,

firebase-perf/src/main/java/com/google/firebase/perf/transport/TransportManager.java

@@ -14,7 +14,7 @@
 
 package com.google.firebase.perf.transport;
 
-import static com.google.firebase.sessions.ProcessDetailsProvider.getProcessDetailsProvider;
+import static com.google.firebase.perf.util.AppProcessesProvider.getProcessName;
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
 import static java.util.concurrent.TimeUnit.MINUTES;
 
@@ -231,8 +231,7 @@ private void finishInitialization() {
     applicationInfoBuilder = ApplicationInfo.newBuilder();
     applicationInfoBuilder
         .setGoogleAppId(firebaseApp.getOptions().getApplicationId())
-        .setProcessName(
-            getProcessDetailsProvider().getCurrentProcessDetails(appContext).getProcessName())
+        .setProcessName(getProcessName(appContext))
         .setAndroidAppInfo(
             AndroidApplicationInfo.newBuilder()
                 .setPackageName(packageName)

firebase-perf/src/main/java/com/google/firebase/perf/util/AppProcessesProvider.kt

@@ -0,0 +1,73 @@
+// Copyright 2025 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+//
+// You may obtain a copy of the License at
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.firebase.perf.util
+
+import android.app.ActivityManager
+import android.app.Application
+import android.content.Context
+import android.os.Build
+import android.os.Process
+import com.google.android.gms.common.util.ProcessUtils
+
+/**
+ * A singleton that contains helper functions to get relevant process details. TODO(b/418041083):
+ * Explore using a common utility. See [com.google.firebase.sessions.ProcessDetailsProvider].
+ */
+object AppProcessesProvider {
+  /** Gets the details for all of this app's running processes. */
+  @JvmStatic
+  fun getAppProcesses(context: Context): List<ActivityManager.RunningAppProcessInfo> {
+    val appUid = context.applicationInfo.uid
+    val activityManager = context.getSystemService(Context.ACTIVITY_SERVICE) as? ActivityManager
+    val runningAppProcesses = activityManager?.runningAppProcesses ?: listOf()
+
+    return runningAppProcesses.filterNotNull().filter {
+      // Only collect process info for this app's processes.
+      it.uid == appUid
+    }
+  }
+
+  /**
+   * Gets this app's current process name.
+   *
+   * If the current process details are not found for whatever reason, returns an empty string.
+   */
+  @JvmStatic
+  fun getProcessName(context: Context): String {
+    val pid = Process.myPid()
+    return getAppProcesses(context).find { it.pid == pid }?.processName ?: getProcessName()
+  }
+
+  /** Gets the app's current process name. If it could not be found, return the default. */
+  private fun getProcessName(default: String = ""): String {
+    if (Build.VERSION.SDK_INT > Build.VERSION_CODES.TIRAMISU) {
+      return Process.myProcessName()
+    }
+
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
+      Application.getProcessName()?.let {
+        return it
+      }
+    }
+
+    // GMS core has different ways to get the process name on old api levels.
+    ProcessUtils.getMyProcessName()?.let {
+      return it
+    }
+
+    // Returns default if nothing works.
+    return default
+  }
+}

firebase-sessions/src/main/kotlin/com/google/firebase/sessions/ProcessDetailsProvider.kt

@@ -28,11 +28,7 @@ import com.google.android.gms.common.util.ProcessUtils
  *
  * @hide
  */
-object ProcessDetailsProvider {
-  @JvmStatic
-  fun getProcessDetailsProvider(): ProcessDetailsProvider {
-    return this
-  }
+internal object ProcessDetailsProvider {
   /** Gets the details for all of this app's running processes. */
   fun getAppProcessDetails(context: Context): List<ProcessDetails> {
     val appUid = context.applicationInfo.uid

firebase-sessions/src/main/kotlin/com/google/firebase/sessions/SessionEvent.kt

@@ -81,7 +81,7 @@ internal data class DataCollectionStatus(
 )
 
 /** Container for information about the process */
-data class ProcessDetails(
+internal data class ProcessDetails(
   val processName: String,
   val pid: Int,
   val importance: Int,