Extension Messaging: Implement reply to content script from SW.

This CL adds support to send ExtensionHostMsg_PostMessage IPC from
worker threads. This allows reply to work targeting a Service
Worker.

Bug: 925927
Test: chrome.runtime.sendMessage can use reply callback.
Change-Id: I2c64992847f0f8746a455941a58841e5f1fea8c5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1506009
Commit-Queue: Istiaque Ahmed <lazyboy@chromium.org>
Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#638314}

chrome/browser/extensions/service_worker_messaging_apitest.cc

@@ -82,6 +82,29 @@ IN_PROC_BROWSER_TEST_P(ServiceWorkerMessagingTest, TabToWorkerOneWay) {
   EXPECT_TRUE(test_listener.WaitUntilSatisfied());
 }
 
+// Tests chrome.runtime.sendMessage from content script to SW extension.
+IN_PROC_BROWSER_TEST_P(ServiceWorkerMessagingTest, TabToWorker) {
+  ExtensionTestMessageListener worker_listener("WORKER_RUNNING", false);
+  const Extension* extension = LoadExtension(test_data_dir_.AppendASCII(
+      "service_worker/messaging/send_message_tab_to_worker"));
+  ASSERT_TRUE(extension);
+  EXPECT_TRUE(worker_listener.WaitUntilSatisfied());
+
+  ExtensionTestMessageListener reply_listener("CONTENT_SCRIPT_RECEIVED_REPLY",
+                                              false);
+  reply_listener.set_failure_message("FAILURE");
+
+  {
+    ASSERT_TRUE(StartEmbeddedTestServer());
+    const GURL url =
+        embedded_test_server()->GetURL("/extensions/test_file.html");
+    content::WebContents* new_web_contents = AddTab(browser(), url);
+    EXPECT_TRUE(new_web_contents);
+  }
+
+  EXPECT_TRUE(reply_listener.WaitUntilSatisfied());
+}
+
 INSTANTIATE_TEST_SUITE_P(ServiceWorkerMessagingTestWithNativeBindings,
                          ServiceWorkerMessagingTest,
                          ::testing::Values(NATIVE_BINDINGS));

chrome/test/data/extensions/api_test/service_worker/messaging/send_message_tab_to_worker/content_script.js

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+chrome.runtime.sendMessage('tab->worker', response => {
+  if (response != 'tab->worker->tab') {
+    chrome.test.sendMessage('FAILURE');
+    return;
+  }
+  chrome.test.sendMessage('CONTENT_SCRIPT_RECEIVED_REPLY');
+});

chrome/test/data/extensions/api_test/service_worker/messaging/send_message_tab_to_worker/manifest.json

+{
+  "name": "runtime.sendMessage from content script to SW extension",
+  "version": "0.1",
+  "manifest_version": 2,
+  "description": "service worker",
+  "content_scripts": [{
+    "matches": ["*://*/*"],
+    "js": ["content_script.js"]
+  }],
+  "background": {"service_worker_script": "service_worker_background.js"}
+}

chrome/test/data/extensions/api_test/service_worker/messaging/send_message_tab_to_worker/service_worker_background.js

+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+chrome.runtime.onMessage.addListener((msg, sender, sendResponse) => {
+  if (msg != 'tab->worker') {
+    chrome.test.sendMessage('FAILURE');
+    return;
+  }
+  sendResponse('tab->worker->tab');
+});
+
+chrome.test.sendMessage('WORKER_RUNNING');

extensions/renderer/extension_port.cc

@@ -35,14 +35,15 @@ ExtensionPort::ExtensionPort(ScriptContext* script_context,
 ExtensionPort::~ExtensionPort() {}
 
 void ExtensionPort::PostExtensionMessage(std::unique_ptr<Message> message) {
-  content::RenderFrame* render_frame = script_context_->GetRenderFrame();
-  // TODO(devlin): What should we do if there's no render frame? Up until now,
-  // we've always just dropped the messages, but we might need to figure this
-  // out for service workers.
-  // TODO(crbug.com/925918): Support Service Worker.
-  if (!render_frame)
-    return;
-  render_frame->Send(new ExtensionHostMsg_PostMessage(id_, *message));
+  if (worker_thread_util::IsWorkerThread()) {
+    DCHECK(!script_context_->GetRenderFrame());
+    GetWorkerThreadIPCMessageSender()->SendPostMessageToPort(id_, *message);
+  } else {
+    content::RenderFrame* render_frame = script_context_->GetRenderFrame();
+    if (!render_frame)
+      return;
+    render_frame->Send(new ExtensionHostMsg_PostMessage(id_, *message));
+  }
 }
 
 void ExtensionPort::Close(bool close_channel) {

extensions/renderer/ipc_message_sender.cc

@@ -389,7 +389,7 @@ class WorkerThreadIPCMessageSender : public IPCMessageSender {
 
   void SendPostMessageToPort(const PortId& port_id,
                              const Message& message) override {
-    NOTIMPLEMENTED();
+    dispatcher_->Send(new ExtensionHostMsg_PostMessage(port_id, message));
   }
 
  private: