2.x: Update marble diagrams for sample overloads (#4990)

* 2.x: Update marble diagrams for sample overloads

* Add Maybe and switchIfEmpty diagrams

Author: akarnokd

src/main/java/io/reactivex/Flowable.java

@@ -11611,7 +11611,7 @@ public final Flowable<T> sample(long period, TimeUnit unit) {
      * Returns a Flowable that emits the most recently emitted item (if any) emitted by the source Publisher
      * within periodic time intervals and optionally emit the very last upstream item when the upstream completes.
      * <p>
-     * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.png" alt="">
+     * <img width="408" height="177" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.emitlast.png" alt="">
      * <dl>
      *  <dt><b>Backpressure:</b></dt>
      *  <dd>This operator does not support backpressure as it uses time to control data flow.</dd>
@@ -11680,7 +11680,7 @@ public final Flowable<T> sample(long period, TimeUnit unit, Scheduler scheduler)
      * within periodic time intervals, where the intervals are defined on a particular Scheduler
      * and optionally emit the very last upstream item when the upstream completes.
      * <p>
-     * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.s.png" alt="">
+     * <img width="408" height="177" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.s.emitlast.png" alt="">
      * <dl>
      *  <dt><b>Backpressure:</b></dt>
      *  <dd>This operator does not support backpressure as it uses time to control data flow.</dd>
@@ -11720,7 +11720,7 @@ public final Flowable<T> sample(long period, TimeUnit unit, Scheduler scheduler,
      * emits the most recently emitted item (if any) emitted by the source Publisher since the previous
      * emission from the {@code sampler} Publisher.
      * <p>
-     * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.o.png" alt="">
+     * <img width="437" height="198" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.o.nolast.png" alt="">
      * <dl>
      *  <dt><b>Backpressure:</b></dt>
      *  <dd>This operator does not support backpressure as it uses the emissions of the {@code sampler}
@@ -11751,7 +11751,7 @@ public final <U> Flowable<T> sample(Publisher<U> sampler) {
      * emission from the {@code sampler} Publisher
      * and optionally emit the very last upstream item when the upstream or other Publisher complete.
      * <p>
-     * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.o.png" alt="">
+     * <img width="437" height="198" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.o.emitlast.png" alt="">
      * <dl>
      *  <dt><b>Backpressure:</b></dt>
      *  <dd>This operator does not support backpressure as it uses the emissions of the {@code sampler}
@@ -12877,6 +12877,7 @@ public final Flowable<T> subscribeOn(Scheduler scheduler) {
     /**
      * Returns a Flowable that emits the items emitted by the source Publisher or the items of an alternate
      * Publisher if the source Publisher is empty.
+     * <img width="410" height="164" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/switchifempty.png" alt="">
      * <p/>
      * <dl>
      *  <dt><b>Backpressure:</b></dt>

src/main/java/io/reactivex/Maybe.java

@@ -35,6 +35,8 @@
 /**
  * Represents a deferred computation and emission of a maybe value or exception.
  * <p>
+ * <img width="403" height="233" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/maybe.png" alt="">
+ * <p>
  * The main consumer type of Maybe is {@link MaybeObserver} whose methods are called
  * in a sequential fashion following this protocol:<br>
  * {@code onSubscribe (onSuccess | onError | onComplete)?}.
@@ -3768,6 +3770,8 @@ public final <E extends MaybeObserver<? super T>> E subscribeWith(E observer) {
     /**
      * Returns a Maybe that emits the items emitted by the source Maybe or the items of an alternate
      * MaybeSource if the current Maybe is empty.
+     * <p>
+     * <img width="441" height="307" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/switchifempty.m.png" alt="">
      * <p/>
      * <dl>
      *  <dt><b>Scheduler:</b></dt>

src/main/java/io/reactivex/Observable.java

@@ -9687,7 +9687,7 @@ public final Observable<T> sample(long period, TimeUnit unit) {
      * Returns an Observable that emits the most recently emitted item (if any) emitted by the source ObservableSource
      * within periodic time intervals and optionally emit the very last upstream item when the upstream completes.
      * <p>
-     * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.png" alt="">
+     * <img width="408" height="177" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.emitlast.png" alt="">
      * <dl>
      *  <dt><b>Scheduler:</b></dt>
      *  <dd>{@code sample} operates by default on the {@code computation} {@link Scheduler}.</dd>
@@ -9748,7 +9748,7 @@ public final Observable<T> sample(long period, TimeUnit unit, Scheduler schedule
      * within periodic time intervals, where the intervals are defined on a particular Scheduler
      *  and optionally emit the very last upstream item when the upstream completes.
      * <p>
-     * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.s.png" alt="">
+     * <img width="408" height="177" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.s.emitlast.png" alt="">
      * <dl>
      *  <dt><b>Scheduler:</b></dt>
      *  <dd>You specify which {@link Scheduler} this operator will use</dd>
@@ -9784,9 +9784,8 @@ public final Observable<T> sample(long period, TimeUnit unit, Scheduler schedule
      * emits the most recently emitted item (if any) emitted by the source ObservableSource since the previous
      * emission from the {@code sampler} ObservableSource.
      * <p>
-     * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.o.png" alt="">
+     * <img width="437" height="198" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.o.nolast.png" alt="">
      * <dl>
-     *      ObservableSource to control data flow.</dd>
      *  <dt><b>Scheduler:</b></dt>
      *  <dd>This version of {@code sample} does not operate by default on a particular {@link Scheduler}.</dd>
      * </dl>
@@ -9811,9 +9810,8 @@ public final <U> Observable<T> sample(ObservableSource<U> sampler) {
      * emission from the {@code sampler} ObservableSource
      * and optionally emit the very last upstream item when the upstream or other ObservableSource complete.
      * <p>
-     * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.o.png" alt="">
+     * <img width="437" height="198" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.o.emitlast.png" alt="">
      * <dl>
-     *      ObservableSource to control data flow.</dd>
      *  <dt><b>Scheduler:</b></dt>
      *  <dd>This version of {@code sample} does not operate by default on a particular {@link Scheduler}.</dd>
      * </dl>
@@ -10766,6 +10764,7 @@ public final Observable<T> subscribeOn(Scheduler scheduler) {
     /**
      * Returns an Observable that emits the items emitted by the source ObservableSource or the items of an alternate
      * ObservableSource if the source ObservableSource is empty.
+     * <img width="410" height="164" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/switchifempty.png" alt="">
      * <p/>
      * <dl>
      *  <dt><b>Scheduler:</b></dt>