Fix flaky CertificateProviderApiTest.Basic test.

chrome/browser/extensions/api/certificate_provider/certificate_provider_apitest.cc

 // Copyright 2015 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 <openssl/evp.h>
 #include <openssl/rsa.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdlib.h>
 
@@ skipping 141 matching lines @@
 
     content::RunAllPendingInMessageLoop();
   }
 
  protected:
   policy::MockConfigurationPolicyProvider provider_;
 };
 
 }  // namespace
 
-// See crbug.com/576364 for details
-#if defined(OS_CHROMEOS)
-#define MAYBE_Basic DISABLED_Basic
-#else
-#define MAYBE_Basic Basic
-#endif
-IN_PROC_BROWSER_TEST_F(CertificateProviderApiTest, MAYBE_Basic) {
+IN_PROC_BROWSER_TEST_F(CertificateProviderApiTest, Basic) {
   // Start an HTTPS test server that requests a client certificate.
   net::SpawnedTestServer::SSLOptions ssl_options;
   ssl_options.request_client_certificate = true;
   net::SpawnedTestServer https_server(net::SpawnedTestServer::TYPE_HTTPS,
                                       ssl_options, base::FilePath());
   ASSERT_TRUE(https_server.Start());
 
   extensions::ResultCatcher catcher;
 
   const base::FilePath extension_path =
@@ skipping 11 matching lines @@
   content::TestNavigationObserver navigation_observer(
       nullptr /* no WebContents */);
   navigation_observer.StartWatchingNewWebContents();
   ui_test_utils::NavigateToURLWithDisposition(
       browser(), https_server.GetURL("client-cert"), NEW_FOREGROUND_TAB,
       ui_test_utils::BROWSER_TEST_NONE);
 
   content::WebContents* const https_contents =
       browser()->tab_strip_model()->GetActiveWebContents();
 
+  VLOG(1) << "Wait for the extension to respond to the certificates request.";
+  ASSERT_TRUE(catcher.GetNextResult()) << catcher.message();
+
   VLOG(1) << "Wait for the extension to receive the sign request.";
   ASSERT_TRUE(catcher.GetNextResult()) << catcher.message();
 
   VLOG(1) << "Fetch the digest from the sign request.";
   std::vector<uint8_t> request_digest;
   {
     base::RunLoop run_loop;
     extension_contents->GetMainFrame()->ExecuteJavaScriptForTests(
         base::ASCIIToUTF16("signDigestRequest.digest;"),
         base::Bind(&StoreDigest, &request_digest, run_loop.QuitClosure()));
@@ skipping 53 matching lines @@
     base::RunLoop run_loop;
     const std::string code = "replyWithSignatureSecondTime();";
     bool result = false;
     extension_contents->GetMainFrame()->ExecuteJavaScriptForTests(
         base::ASCIIToUTF16(code),
         base::Bind(&StoreBool, &result, run_loop.QuitClosure()));
     run_loop.Run();
     EXPECT_TRUE(result);
   }
 }