Add DumpAccessibilityEvents test framework.

content/browser/accessibility/dump_accessibility_browsertest_base.cc

 // Copyright (c) 2014 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 "content/browser/accessibility/dump_accessibility_browsertest_base.h"
 
 #include <set>
 #include <string>
 #include <vector>
 
@@ skipping 29 matching lines @@
 
 base::string16
 DumpAccessibilityTestBase::DumpUnfilteredAccessibilityTreeAsString() {
   WebContentsImpl* web_contents = static_cast<WebContentsImpl*>(
       shell()->web_contents());
   AccessibilityTreeFormatter formatter(
       web_contents->GetRootBrowserAccessibilityManager()->GetRoot());
   std::vector<Filter> filters;
   filters.push_back(Filter(base::ASCIIToUTF16("*"), Filter::ALLOW));
   formatter.SetFilters(filters);
+  formatter.set_show_ids(true);
   base::string16 ax_tree_dump;
   formatter.FormatAccessibilityTree(&ax_tree_dump);
   return ax_tree_dump;
 }
 
 std::vector<int> DumpAccessibilityTestBase::DiffLines(
     const std::vector<std::string>& expected_lines,
     const std::vector<std::string>& actual_lines) {
   int actual_lines_count = actual_lines.size();
   int expected_lines_count = expected_lines.size();
@@ skipping 174 matching lines @@
     EXPECT_TRUE(base::WriteFile(
         actual_file, actual_contents.c_str(), actual_contents.size()));
 
     ADD_FAILURE() << "No expectation found. Create it by doing:\n"
                   << "mv " << actual_file.LossyDisplayName() << " "
                   << expected_file.LossyDisplayName();
   }
 }
 
 }  // namespace content