Periodically post available live data, even when invalidated

app/src/main/java/androidx/lifecycle/ComputableLiveData.java

@@ -16,6 +16,8 @@
 
 package androidx.lifecycle;
 
+import android.os.SystemClock;
+
 import androidx.annotation.MainThread;
 import androidx.annotation.NonNull;
 import androidx.annotation.RestrictTo;
@@ -89,14 +91,22 @@ public abstract class ComputableLiveData<T> {
         @Override
         public void run() {
             boolean computed;
+            long age;
             do {
                 computed = false;
                 // compute can happen only in 1 thread but no reason to lock others.
                 if (mComputing.compareAndSet(false, true)) {
                     // as long as it is invalid, keep computing.
                     try {
+                        age = SystemClock.elapsedRealtime();
                         T value = null;
                         while (mInvalid.compareAndSet(true, false)) {
+                            long now = SystemClock.elapsedRealtime();
+                            if (age + 1500 < now && value != null) {
+                                eu.faircode.email.Log.i(mLiveData + " post age=" + (now - age));
+                                age = now;
+                                mLiveData.postValue(value);
+                            }
                             computed = true;
                             value = compute();
                         }