Merge remote-tracking branch 'origin/master' into release/7.2.0

Author: hborisoff

AndroidSDKCore/src/main/java/com/leanplum/LeanplumActivityHelper.java

@@ -200,6 +200,11 @@ public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
    * Enables lifecycle callbacks for Android devices with Android OS >= 4.0
    */
   public static void enableLifecycleCallbacks(final Application app) {
+    if (registeredCallbacks) {
+      // callback is already registered
+      return;
+    }
+
     Leanplum.setApplicationContext(app.getApplicationContext());
 
     if (BuildUtil.shouldDisableTrampolines(app)) {

AndroidSDKPush/src/main/java/com/leanplum/internal/PushActionPersistence.kt

@@ -51,8 +51,14 @@ private fun save(records: Map<String, Long>) {
 }
 
 fun recordOpenAction(occurrenceId: String) {
-    records[occurrenceId] = Clock.getInstance().currentTimeMillis()
-    save(records)
+    synchronized(records) {
+        records[occurrenceId] = Clock.getInstance().currentTimeMillis()
+        save(records)
+    }
 }
 
-fun isOpened(occurrenceId: String) = records.contains(occurrenceId)
+fun isOpened(occurrenceId: String): Boolean {
+    synchronized(records) {
+        return records.contains(occurrenceId)
+    }
+}