Fix Random.nextLong returning value out of range KT-47304

Correctly zero-extend the lower Int part of the Long being produced

libraries/stdlib/src/kotlin/random/Random.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
@@ -135,7 +135,7 @@ public abstract class Random {
                         nextInt().toLong() and 0xFFFF_FFFF
                     else -> {
                         val bitCount = fastLog2(nHigh)
-                        nextBits(bitCount).toLong().shl(32) + nextInt()
+                        nextBits(bitCount).toLong().shl(32) + (nextInt().toLong() and 0xFFFF_FFFF)
                     }
                 }
             } else {