Fix K/N EvenLoop.reschedule time conversion (#4245)

A "point of time" value was wrongly passed to a function that expects a "duration of time".
Additionally, the former was in nanos, while the latter is in milllis.

kotlinx-coroutines-core/concurrent/test/RunBlockingTest.kt

@@ -4,6 +4,8 @@ import kotlinx.coroutines.testing.*
 import kotlinx.coroutines.exceptions.*
 import kotlin.coroutines.*
 import kotlin.test.*
+import kotlin.time.Duration.Companion.milliseconds
+import kotlin.time.Duration.Companion.seconds
 
 class RunBlockingTest : TestBase() {
 
@@ -176,4 +178,20 @@ class RunBlockingTest : TestBase() {
             }
         }
     }
+
+    /** Tests that the delayed tasks scheduled on a closed `runBlocking` event loop get processed in reasonable time. */
+    @Test
+    fun testReschedulingDelayedTasks() {
+        val job = runBlocking {
+            val dispatcher = coroutineContext[ContinuationInterceptor]!!
+            GlobalScope.launch(dispatcher) {
+                delay(1.milliseconds)
+            }
+        }
+        runBlocking {
+            withTimeout(10.seconds) {
+                job.join()
+            }
+        }
+    }
 }

kotlinx-coroutines-core/native/src/EventLoop.kt

@@ -15,7 +15,8 @@ internal actual abstract class EventLoopImplPlatform : EventLoop() {
     }
 
     protected actual fun reschedule(now: Long, delayedTask: EventLoopImplBase.DelayedTask) {
-        DefaultExecutor.invokeOnTimeout(now, delayedTask, EmptyCoroutineContext)
+        val delayTimeMillis = delayNanosToMillis(delayedTask.nanoTime - now)
+        DefaultExecutor.invokeOnTimeout(delayTimeMillis, delayedTask, EmptyCoroutineContext)
     }
 }