Implement <extensionoptions> deferred attach logic

chrome/test/data/extensions/api_test/extension_options/embed_self/test.js

Index: chrome/test/data/extensions/api_test/extension_options/embed_self/test.js
diff --git a/chrome/test/data/extensions/api_test/extension_options/embed_self/test.js b/chrome/test/data/extensions/api_test/extension_options/embed_self/test.js
index 69a8a6999fc211df288b7d9b20f1f7500b0b034a..892c431a6d923ca839d6b79deb2f4326dfa9d0be 100644
--- a/chrome/test/data/extensions/api_test/extension_options/embed_self/test.js
+++ b/chrome/test/data/extensions/api_test/extension_options/embed_self/test.js
@@ -47,6 +47,22 @@ chrome.test.runTests([
     document.body.appendChild(extensionoptions);
   },
 
+  function createGuestViewDeferredAttach() {
+    var extensionoptions = new ExtensionOptions();
+    extensionoptions.onload = function() {
+      try {
+        chrome.test.assertTrue(optionsPageLoaded());
+        chrome.test.succeed();
+      } finally {
+        document.body.removeChild(extensionoptions);
+      }
+    };
+    extensionoptions.extension = chrome.runtime.id;
+    setTimeout(function() {
+      document.body.appendChild(extensionoptions);
+    }, 1000);

[not at google - send to devlin, 2014/08/12 19:58:29]

Why 1000? Just make it 0, no need to make this test run 1s longer than it needs
to.

[ericzeng, 2014/08/12 21:53:33]

Unfortunately I need a small delay in order to reproduce the bug. If appendChild
is run immediately after the extension id is set it looks like the browser
plugin can be initialized in time for extensionoptions to call attach. I can
shorten it but the delay needs to be there to prevent the race from occurring.

+  },
+
   // Tests if the <extensionoptions> guest view is successfully created and can
   // communicate with the embedder. This test expects that the guest options
   // page will add a {'pass': true} property to every Window and fire the