Fix loading success.html at the end of chrome://chrome-signin flow

chrome/browser/ui/webui/signin/inline_login_ui_browsertest.cc

Index: chrome/browser/ui/webui/signin/inline_login_ui_browsertest.cc
diff --git a/chrome/browser/ui/webui/signin/inline_login_ui_browsertest.cc b/chrome/browser/ui/webui/signin/inline_login_ui_browsertest.cc
index 23515fd9c2b79cda1183a074463a5311120b976e..1158907441c3ac2416ffaccd9f23a31cde5cc27a 100644
--- a/chrome/browser/ui/webui/signin/inline_login_ui_browsertest.cc
+++ b/chrome/browser/ui/webui/signin/inline_login_ui_browsertest.cc
@@ -865,6 +865,32 @@ IN_PROC_BROWSER_TEST_F(InlineLoginUISafeIframeBrowserTest, NoWebUIInIframe) {
   ui_test_utils::NavigateToURL(browser(), url);
 }
 
+// Make sure that "success.html" can be loaded by chrome://chrome-signin.
+// http://crbug.com/709117
+IN_PROC_BROWSER_TEST_F(InlineLoginUISafeIframeBrowserTest,
+                       LoadSuccessContinueURL) {
+  ui_test_utils::NavigateToURL(browser(), GetSigninPromoURL());
+  WaitUntilUIReady(browser());
+
+  const std::string success_url =
+      GaiaUrls::GetInstance()->signin_completed_continue_url().spec();
+  const char* kLoadSuccessPageScript =
+      "var handler = function(e) {"
+      "  if (e.url == '%s') {"
+      "    window.domAutomationController.send('success_page_loaded');"
+      "  }"
+      "};"
+      "var extension_webview = inline.login.getAuthExtHost().webview_;"
+      "extension_webview.addEventListener('loadcommit', handler);"
+      "extension_webview.src = '%s';";
+  std::string script = base::StringPrintf(
+      kLoadSuccessPageScript, success_url.c_str(), success_url.c_str());
+
+  std::string message;
+  ASSERT_TRUE(content::ExecuteScriptAndExtractString(

[xiyuan, 2017/04/27 15:55:45]

I don't think this waits for 'loadcommit' handler to send back message. It would
return after the script is executed. We need to manually wait for the expected
message to return.

i.e.
  content::DOMMessageQueue message_queue;
  ASSERT_TRUE(content::ExecuteScriptAndExtractString(...));
  std::string message;
  do {
    ASSERT_TRUE(message_queue.WaitForMessage(&message));
  } while (message != "\"success_page_loaded\"");
  

[msarda, 2017/04/27 15:59:39]

It does wait to get a response message in the content::DOMMessageQueue (see
https://cs.chromium.org/chromium/src/content/public/test/browser_test_utils.c...).
In my tests, this waits as expected.

This is the same approach we're using for WaitUntilUIReady(browser());

[xiyuan, 2017/04/27 16:16:24]

Okay. At least, we should add an ASSERT_EQ to guarantee |message| is the
expected "success_page_loaded".

[Charlie Reis, 2017/04/27 16:26:33]

Agreed-- no need to loop, but verifying the right message came through is
worthwhile.

[msarda, 2017/04/27 16:48:51]

Done (I had it locally and  I think I removed that by mistake. Thank you for
catching it.)

+      browser()->tab_strip_model()->GetActiveWebContents(), script, &message));
+}
+
 // Make sure that the gaia iframe cannot trigger top-frame navigation.
 // TODO(guohui): flaky on trybot crbug/364759.
 IN_PROC_BROWSER_TEST_F(InlineLoginUISafeIframeBrowserTest,