Sprinkle some defensiveness into the UI tests so that they don't explode if t...

chrome/test/ui/dom_checker_uitest.cc

 // Copyright (c) 2009 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 "base/command_line.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/scoped_ptr.h"
 #include "base/string_util.h"
 #include "base/values.h"
@@ skipping 182 matching lines @@
       url_string.append(test_directory);
       url_string.append(start_file);
       test_url = GURL(url_string);
     } else {
       FilePath test_path = GetDomCheckerDir();
       test_path = test_path.Append(start_file);
       test_url = net::FilePathToFileURL(test_path);
     }
 
     scoped_refptr<TabProxy> tab(GetActiveTab());
+    ASSERT_TRUE(tab.get());
     tab->NavigateToURL(test_url);
 
     // Wait for the test to finish.
     ASSERT_TRUE(WaitUntilTestCompletes(tab.get()));
 
     // Get the test results.
     ASSERT_TRUE(GetTestCount(tab.get(), test_count));
     ASSERT_TRUE(GetTestsFailed(tab.get(), tests_failed));
     ASSERT_GT(*test_count, 0);
   }
@@ skipping 13 matching lines @@
 TEST_F(DomCheckerTest, Http) {
   if (!CommandLine::ForCurrentProcess()->HasSwitch(kRunDomCheckerTest))
     return;
 
   ResultsList new_passes, new_failures;
   RunTest(true, &new_passes, &new_failures);
   PrintResults(new_passes, new_failures);
 }
 
 }  // namespace