[Media Router tests] Fix MANUAL_Fail_StartCancelledNoSupportedSinks.

chrome/test/media_router/media_router_integration_browsertest.h

 // 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.
 
 #ifndef CHROME_TEST_MEDIA_ROUTER_MEDIA_ROUTER_INTEGRATION_BROWSERTEST_H_
 #define CHROME_TEST_MEDIA_ROUTER_MEDIA_ROUTER_INTEGRATION_BROWSERTEST_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 56 matching lines @@
   // |web_contents|: The web contents of the test page which invokes the popup
   //                 dialog.
   content::WebContents* GetMRDialog(content::WebContents* web_contents);
 
   // Checks that the chrome modal dialog does not exist.
   bool IsDialogClosed(content::WebContents* web_contents);
   void WaitUntilDialogClosed(content::WebContents* web_contents);
 
   void CheckDialogRemainsOpen(content::WebContents* web_contents);
 
-  // Opens "basic_test.html," and starts a presentation.
-  content::WebContents* StartSessionWithTestPageNow();
+  // Opens "basic_test.html" and asserts that attempting to start a presentation
+  // fails with NotFoundError due to no sinks available.
+  void StartSessionAndAssertNotFoundError();
+
   // Opens "basic_test.html," waits for sinks to be available, and starts a
   // presentation.
   content::WebContents* StartSessionWithTestPageAndSink();
 
   // Opens "basic_test.html," waits for sinks to be available, starts a
   // presentation, and chooses a sink with the name |kTestSinkName|. Also checks
   // that the presentation has successfully started if |should_succeed| is true.
   content::WebContents* StartSessionWithTestPageAndChooseSink();
 
   void OpenTestPage(base::FilePath::StringPieceType file);
@@ skipping 102 matching lines @@
   Browser* browser() override;
 
  private:
   Browser* incognito_browser_ = nullptr;
   std::string incognito_extension_id_;
 };
 
 }  // namespace media_router
 
 #endif  // CHROME_TEST_MEDIA_ROUTER_MEDIA_ROUTER_INTEGRATION_BROWSERTEST_H_