Merge branch '2.x' of https://github.com/ReactiveX/RxJava.git into 2.x

Author: akarnokd

src/main/java/io/reactivex/internal/operators/flowable/FlowableTimeoutTimed.java

@@ -14,14 +14,12 @@
 package io.reactivex.internal.operators.flowable;
 
 import java.util.concurrent.*;
-import java.util.concurrent.atomic.AtomicReference;
 
 import org.reactivestreams.*;
 
 import io.reactivex.*;
 import io.reactivex.Scheduler.Worker;
 import io.reactivex.disposables.Disposable;
-import io.reactivex.internal.disposables.DisposableHelper;
 import io.reactivex.internal.subscribers.FullArbiterSubscriber;
 import io.reactivex.internal.subscriptions.*;
 import io.reactivex.plugins.RxJavaPlugins;