[Extensions] DCHECK that ExtensionFunctions respond (and only once)

chrome/browser/extensions/lazy_background_page_apitest.cc

 // Copyright (c) 2012 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.
 
 #include <stddef.h>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/path_service.h"
@@ skipping 557 matching lines @@
 
   ExtensionTestMessageListener page_ready("ready", true);
   GURL page_url = extension->GetResourceURL("page.html");
   ui_test_utils::NavigateToURL(browser(), page_url);
   EXPECT_TRUE(page_ready.WaitUntilSatisfied());
 
   // After the event is sent below, wait for the event page to have received
   // the event before proceeding with the test.  This allows the regular page
   // to test that the event page received the event, which makes the pass/fail
   // logic simpler.
-  ExtensionTestMessageListener event_page_ready("ready", true);
+  ExtensionTestMessageListener event_page_ready("ready", false);
 
   // Send an event by making a bookmark.
   BookmarkModel* bookmark_model =
       BookmarkModelFactory::GetForProfile(browser()->profile());
   bookmarks::test::WaitForBookmarkModelToLoad(bookmark_model);
   bookmarks::AddIfNotBookmarked(bookmark_model,
                                 GURL("http://www.google.com"),
                                 base::UTF8ToUTF16("Google"));
 
   EXPECT_TRUE(event_page_ready.WaitUntilSatisfied());
@@ skipping 64 matching lines @@
 // handler calls an API function such as chrome.storage.local.set().
 // See: http://crbug.com/296834
 IN_PROC_BROWSER_TEST_F(LazyBackgroundPageApiTest, OnSuspendUseStorageApi) {
   EXPECT_TRUE(LoadExtensionAndWait("on_suspend"));
 }
 
 // TODO: background page with timer.
 // TODO: background page that interacts with popup.
 
 }  // namespace extensions