8024178: Difference in Stream.collect(Collector) methods located in jdk8 and jdk8-lambda repos

Reviewed-by: mduigou

src/share/classes/java/util/stream/DelegatingStream.java

@@ -209,7 +209,7 @@ public class DelegatingStream<T> implements Stream<T> {
     }
 
     @Override
-    public <R, A> R collect(Collector<? super T, A, ? extends R> collector) {
+    public <R, A> R collect(Collector<? super T, A, R> collector) {
         return delegate.collect(collector);
     }
 

src/share/classes/java/util/stream/ReferencePipeline.java

@@ -493,7 +493,7 @@ abstract class ReferencePipeline<P_IN, P_OUT>
 
     @Override
     @SuppressWarnings("unchecked")
-    public final <R, A> R collect(Collector<? super P_OUT, A, ? extends R> collector) {
+    public final <R, A> R collect(Collector<? super P_OUT, A, R> collector) {
         A container;
         if (isParallel()
                 && (collector.characteristics().contains(Collector.Characteristics.CONCURRENT))

src/share/classes/java/util/stream/Stream.java

@@ -657,7 +657,7 @@ public interface Stream<T> extends BaseStream<T, Stream<T>> {
      * @see #collect(Supplier, BiConsumer, BiConsumer)
      * @see Collectors
      */
-    <R, A> R collect(Collector<? super T, A, ? extends R> collector);
+    <R, A> R collect(Collector<? super T, A, R> collector);
 
     /**
      * Returns the minimum element of this stream according to the provided