Add Observable for LiveRecipient.

app/src/main/java/org/thoughtcrime/securesms/recipients/LiveRecipient.java

@@ -30,6 +30,7 @@ import java.util.concurrent.CopyOnWriteArraySet;
 import java.util.concurrent.atomic.AtomicReference;
 
 import io.reactivex.rxjava3.core.Observable;
+import io.reactivex.rxjava3.subjects.BehaviorSubject;
 
 public final class LiveRecipient {
 
@@ -41,15 +42,17 @@ public final class LiveRecipient {
   private final LiveData<Recipient>           observableLiveDataResolved;
   private final Set<RecipientForeverObserver> observers;
   private final Observer<Recipient>           foreverObserver;
-  private final AtomicReference<Recipient> recipient;
-  private final RecipientTable             recipientTable;
-  private final GroupTable                 groupDatabase;
-  private final DistributionListTables distributionListTables;
-  private final MutableLiveData<Object> refreshForceNotify;
+  private final AtomicReference<Recipient>    recipient;
+  private final RecipientTable                recipientTable;
+  private final GroupTable                    groupDatabase;
+  private final DistributionListTables        distributionListTables;
+  private final MutableLiveData<Object>       refreshForceNotify;
+  private final BehaviorSubject<Recipient>    subject;
 
   LiveRecipient(@NonNull Context context, @NonNull Recipient defaultRecipient) {
     this.context                  = context.getApplicationContext();
     this.liveData                 = new MutableLiveData<>(defaultRecipient);
+    this.subject                  = BehaviorSubject.createDefault(defaultRecipient);
     this.recipient                = new AtomicReference<>(defaultRecipient);
     this.recipientTable           = SignalDatabase.recipients();
     this.groupDatabase            = SignalDatabase.groups();
@@ -80,6 +83,13 @@ public final class LiveRecipient {
     return recipient.get();
   }
 
+  /**
+   * @return An rx-flavored {@link Observable}.
+   */
+  public @NonNull Observable<Recipient> observable() {
+    return subject.distinctUntilChanged(Recipient::hasSameContent);
+  }
+
   /**
    * Watch the recipient for changes. The callback will only be invoked if the provided lifecycle is
    * in a valid state. No need to remove the observer. If you do wish to remove the observer (if,
@@ -97,19 +107,6 @@ public final class LiveRecipient {
     ThreadUtil.runOnMain(() -> observableLiveData.removeObservers(owner));
   }
 
-  public Observable<Recipient> asObservable() {
-    return Observable.create(emitter -> {
-      Recipient current = recipient.get();
-      if (current != null && current.getId() != RecipientId.UNKNOWN) {
-        emitter.onNext(current);
-      }
-
-      RecipientForeverObserver foreverObserver = emitter::onNext;
-      observeForever(foreverObserver);
-      emitter.setCancellable(() -> removeForeverObserver(foreverObserver));
-    });
-  }
-
   /**
    * Watch the recipient for changes. The callback could be invoked at any time. You MUST call
    * {@link #removeForeverObserver(RecipientForeverObserver)} when finished. You should use
@@ -243,6 +240,7 @@ public final class LiveRecipient {
   synchronized void set(@NonNull Recipient recipient) {
     this.recipient.set(recipient);
     this.liveData.postValue(recipient);
+    this.subject.onNext(recipient);
   }
 
   @Override