refactor(core): Allow multiple overflown responses in single poll (#9433)

This commit rewrites "JsRuntime::poll" function to fix a corner case that
might caused "overflown_response" to be overwritten by other overflown response.

The logic has been changed to allow returning multiple overflown response
alongside responses from shared queue.

1 files changed, 14 insertions, 0 deletions

diff --git a/cli/tests/workers/large_message_worker.js b/cli/tests/workers/large_message_worker.js
new file mode 100644
index 000000000..f7b7da8a0
--- /dev/null
+++ b/cli/tests/workers/large_message_worker.js
@@ -0,0 +1,14 @@
+// Copyright 2020 the Deno authors. All rights reserved. MIT license.
+
+const dataSmall = "";
+const dataLarge = "x".repeat(10 * 1024);
+
+onmessage = function (e) {
+  for (let i = 0; i <= 10; i++) {
+    if (i % 2 == 0) {
+      postMessage(dataLarge);
+    } else {
+      postMessage(dataSmall);
+    }
+  }
+};