Reset on_bailout pointer to NULL when reactivating the coroutine sche…

…duler

src/coroutine/base.cc

@@ -43,6 +43,7 @@ void Coroutine::activate() {
     coroutine::thread_context_init();
 #endif
     activated = true;
+    on_bailout = nullptr;
 }
 
 void Coroutine::deactivate() {

tests/swoole_coroutine_scheduler/repeat.phpt

@@ -0,0 +1,35 @@
+--TEST--
+swoole_coroutine_scheduler: user yield and resume1
+--SKIPIF--
+<?php require __DIR__ . '/../include/skipif.inc'; ?>
+--FILE--
+<?php
+require __DIR__ . '/../include/bootstrap.php';
+
+\Swoole\Coroutine\run(function () {
+    echo 'scheduler 1: begin' . PHP_EOL;
+    Swoole\Coroutine\System::sleep(0.1);
+    echo 'scheduler 1: end' . PHP_EOL;
+});
+
+echo 'sleep: begin' . PHP_EOL;
+usleep(100_000);
+echo 'sleep: end' . PHP_EOL;
+
+\Swoole\Coroutine\run(function () {
+    echo 'scheduler 2: begin' . PHP_EOL;
+    Swoole\Coroutine\System::sleep(0.1);
+    echo 'scheduler 2: end' . PHP_EOL;
+});
+
+echo 'DONE' . PHP_EOL;
+
+?>
+--EXPECT--
+scheduler 1: begin
+scheduler 1: end
+sleep: begin
+sleep: end
+scheduler 2: begin
+scheduler 2: end
+DONE