Small code refactoring

Author: ndkoval

kotlinx-coroutines-core/common/src/channels/AbstractChannel.kt

@@ -494,7 +494,7 @@ internal abstract class AbstractChannel<E>(
             // Too late, already cancelled, but we removed it from the queue and need to notify on undelivered element.
             // The only exception is when this "send" operation is an `onSend` clause that has to be re-registered
             // in the corresponding `select` invocation.
-            if (send !is SendElementSelectWithUndeliveredHandler<*> || send.trySelectResult != REREGISTER)
+            if (!(send is SendElementSelectWithUndeliveredHandler<*> && send.trySelectResult == REREGISTER))
                 send.undeliveredElement()
         }
     }

kotlinx-coroutines-core/common/src/channels/ArrayChannel.kt

@@ -158,9 +158,9 @@ internal open class ArrayChannel<E>(
                     // Too late, already cancelled, but we removed it from the queue and need to notify on undelivered element.
                     // The only exception is when this "send" operation is an `onSend` clause that has to be re-registered
                     // in the corresponding `select` invocation.
-                    val send = send
-                    if (send !is SendElementSelectWithUndeliveredHandler<*> || send.trySelectResult != REREGISTER)
-                        send!!.undeliveredElement()
+                    val send = send!!
+                    if (!(send is SendElementSelectWithUndeliveredHandler<*> && send.trySelectResult == REREGISTER))
+                        send.undeliveredElement()
                 }
             }
             if (replacement !== POLL_FAILED && replacement !is Closed<*>) {