Merge pull request ReactiveX#1951 from abersnaze/unnecessary

Remove extraneous request(n) and onCompleted() calls when unsubscribed.

Author: benjchristensen

src/main/java/rx/internal/operators/OnSubscribeFromIterable.java

@@ -98,7 +98,9 @@ public void request(long n) {
                         }
 
                         if (!it.hasNext()) {
-                            o.onCompleted();
+                            if (!o.isUnsubscribed()) {
+                                o.onCompleted();
+                            }
                             return;
                         }
                         if (REQUESTED_UPDATER.addAndGet(this, -r) == 0) {

src/main/java/rx/internal/operators/OperatorMerge.java

@@ -186,7 +186,8 @@ private void handleNewSource(Observable<? extends T> t) {
             InnerSubscriber<T> i = new InnerSubscriber<T>(this, producerIfNeeded);
             i.sindex = childrenSubscribers.add(i);
             t.unsafeSubscribe(i);
-            request(1);
+            if (!isUnsubscribed())
+                request(1);
         }
 
         private void handleScalarSynchronousObservable(ScalarSynchronousObservable<? extends T> t) {