Fix minor CHECKED_RETURN Coverity complaint in code I added to the --diagnost...

chrome/browser/diagnostics/recon_diagnostics.cc

 // Copyright (c) 2011 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 "chrome/browser/diagnostics/recon_diagnostics.h"
 
 #include <string>
 
 #include "base/file_util.h"
 #include "base/json/json_reader.h"
@@ skipping 79 matching lines @@
     ListValue* list = model->GetModuleList();
     if (!model->confirmed_bad_modules_detected() &&
         !model->suspected_bad_modules_detected()) {
       RecordSuccess(ASCIIToUTF16("No conflicting modules found"));
       return true;
     }
 
     string16 failures = ASCIIToUTF16("Possibly conflicting modules:");
     DictionaryValue* dictionary;
     for (size_t i = 0; i < list->GetSize(); ++i) {
-      list->GetDictionary(i, &dictionary);
+      if (!list->GetDictionary(i, &dictionary))
+        RecordFailure(ASCIIToUTF16("Dictionary lookup failed"));
       int status;
       string16 location;
       string16 name;
       if (!dictionary->GetInteger("status", &status))
         RecordFailure(ASCIIToUTF16("No 'status' field found"));
       if (status < ModuleEnumerator::SUSPECTED_BAD)
         continue;
 
       if (!dictionary->GetString("location", &location)) {
         RecordFailure(ASCIIToUTF16("No 'location' field found"));
@@ skipping 300 matching lines @@
   path = path.Append(chrome::kBookmarksFileName);
   return new JSONTest(path, ASCIIToUTF16("BookMarks JSON"), 2 * kOneMeg);
 }
 
 DiagnosticTest* MakeLocalStateTest() {
   FilePath path;
   PathService::Get(chrome::DIR_USER_DATA, &path);
   path = path.Append(chrome::kLocalStateFilename);
   return new JSONTest(path, ASCIIToUTF16("Local State JSON"), 50 * kOneKilo);
 }