Move the event attach/detach logic on unload from event.js to

chrome/browser/extensions/events_apitest.cc

 // Copyright (c) 2010 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 "chrome/browser/extensions/extension_apitest.h"
 
+#include "extensions/browser/event_router.h"
+#include "extensions/browser/extension_registry.h"
+
+namespace extensions {
+
 IN_PROC_BROWSER_TEST_F(ExtensionApiTest, Events) {
   ASSERT_TRUE(RunExtensionTest("events")) << message_;
 }
+
+// Tests that events are unregistered when an extension page shuts down.
+IN_PROC_BROWSER_TEST_F(ExtensionApiTest, EventsAreUnregistered) {
+  // In this test, page1.html registers for a number of events, then navigates
+  // to page2.html, which should unregister those events. page2.html notifies
+  // pass, by which point the event should have been unregistered.
+  EventRouter* event_router = EventRouter::Get(profile());

[Devlin, 2015/04/13 16:07:07]

nit: Prefer to initialize these closer to their use.

+  ExtensionRegistry* registry = ExtensionRegistry::Get(profile());
+
+  std::string test_extension_name = "events_are_unregistered";
+  ASSERT_TRUE(RunExtensionSubtest(test_extension_name, "page1.html"))
+      << message_;
+
+  // Find the extension we just installed by looking for the path.
+  const Extension* extension =
+      GetExtensionByPath(registry->enabled_extensions(),
+                         test_data_dir_.AppendASCII(test_extension_name));
+  ASSERT_TRUE(extension);
+  std::string id = extension->id();
+
+  // The page has closed, so no matter what all events are no longer listened
+  // to.
+  EXPECT_FALSE(
+      event_router->ExtensionHasEventListener(id, "browserAction.onClicked"));
+  EXPECT_FALSE(
+      event_router->ExtensionHasEventListener(id, "runtime.onStartup"));
+  EXPECT_FALSE(
+      event_router->ExtensionHasEventListener(id, "runtime.onSuspend"));
+  EXPECT_FALSE(
+      event_router->ExtensionHasEventListener(id, "runtime.onInstalled"));
+}
+
+}  // namespace extensions