Revert "Extensions: tab.title should not be undefined."

chrome/browser/extensions/extension_tabs_module.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 "chrome/browser/extensions/extension_tabs_module.h"
 
 #include "base/gfx/jpeg_codec.h"
 #include "base/string_util.h"
 #include "chrome/browser/browser.h"
 #include "chrome/browser/browser_list.h"
@@ skipping 97 matching lines @@
 
   DictionaryValue* result = new DictionaryValue();
   result->SetInteger(keys::kIdKey, ExtensionTabUtil::GetTabId(contents));
   result->SetInteger(keys::kIndexKey, tab_index);
   result->SetInteger(keys::kWindowIdKey,
                      ExtensionTabUtil::GetWindowIdOfTab(contents));
   result->SetString(keys::kUrlKey, contents->GetURL().spec());
   result->SetString(keys::kStatusKey, GetTabStatusText(status));
   result->SetBoolean(keys::kSelectedKey,
                      tab_strip && tab_index == tab_strip->selected_index());
-  result->SetString(keys::kTitleKey, UTF16ToWide(contents->GetTitle()));
 
   if (status != TAB_LOADING) {
+    result->SetString(keys::kTitleKey, UTF16ToWide(contents->GetTitle()));
+
     NavigationEntry* entry = contents->controller().GetActiveEntry();
     if (entry) {
       if (entry->favicon().is_valid())
         result->SetString(keys::kFavIconUrlKey, entry->favicon().url().spec());
     }
   }
 
   return result;
 }
 
@@ skipping 756 matching lines @@
   if (ExtensionTabUtil::GetTabById(tab_id, profile, browser, tab_strip,
                                    contents, tab_index))
     return true;
 
   if (error_message)
     *error_message = ExtensionErrorUtils::FormatErrorMessage(
         keys::kTabNotFoundError, IntToString(tab_id));
 
   return false;
 }