Add MediaError.message

content/browser/media/media_browsertest.h

 // Copyright 2013 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 CONTENT_BROWSER_MEDIA_MEDIA_BROWSERTEST_H_
 #define CONTENT_BROWSER_MEDIA_MEDIA_BROWSERTEST_H_
 
 #include <string>
 
 #include "base/strings/string_split.h"
@@ skipping 21 matching lines @@
   // It uses RunTest() to check for expected test output.
   void RunMediaTestPage(const std::string& html_page,
                         const base::StringPairs& query_params,
                         const std::string& expected_title,
                         bool http);
 
   // Opens a URL and waits for the document title to match any of the waited for
   // titles. Returns the matching title.
   std::string RunTest(const GURL& gurl, const std::string& expected_title);
 
+  // Encodes |original_message| to be used in a URI query parameter suitable for
+  // decoding and usage with DecodeURIComponent in test pages that verify error
+  // message contents.
+  std::string EncodeErrorMessage(const std::string& original_message);

[mlamouri (slow - plz ping), 2017/04/18 12:37:59]

It doesn't sound like you need this to be part of the class but instead could be
part of the anonymous namespace. Any specific reason why it's part of the
header?

[wolenetz, 2017/04/18 17:53:06]

In this particular patch set, you're correct: this method is only locally used
and could be moved to anonymous namespace within the impl
(media_browsertest.cc). However, I foresee we may want to have similar error
message testing later on in other kinds of MediaBrowserTest, so put it here to
make it more obvious that this method is here and help reduce possibility of
eventual duplication of this functionality. No other strong feeling here, so if
you feel strongly, I'll move it to the impl.

+
   // Adds titles that RunTest() should wait for.
   virtual void AddTitlesToAwait(content::TitleWatcher* title_watcher);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_MEDIA_MEDIA_BROWSERTEST_H_