fix reduce to work with new no-wildcards Java reduce

Author: samuelgruetter

language-adaptors/rxjava-scala/src/main/scala/rx/lang/scalaimpl/Observable.scala

@@ -855,8 +855,8 @@ class Observable[+T](val asJava: rx.Observable[_ <: T])
    */
   def reduce[U >: T](f: (U, U) => U): Observable[U] = {
     val func: rx.util.functions.Func2[_ >: U, _ >: U, _ <: U] = f
-    val func2 = func.asInstanceOf[rx.util.functions.Func2[Any, Any, Nothing]]
-    new Observable[U](asJava.reduce(func2))
+    val func2 = func.asInstanceOf[rx.util.functions.Func2[T, T, T]]
+    new Observable[U](asJava.asInstanceOf[rx.Observable[T]].reduce(func2))
   } 
 
   /**

language-adaptors/rxjava-scala/src/main/scala/rx/lang/scalatests/RxScalaDemo.scala

@@ -104,4 +104,8 @@ class RxScalaDemo extends JUnitSuite {
         .subscribe(output(_))
   }
 
+  @Test def testReduce() {
+    assertEquals(10, Observable(1, 2, 3, 4).reduce(_ + _).toBlockingObservable.single)
+  }
+  
 }