Correct const accessors in base/values.(h|cc), Part II (ListValue)

chrome/browser/search_engines/template_url_prepopulate_data.cc

Index: chrome/browser/search_engines/template_url_prepopulate_data.cc
diff --git a/chrome/browser/search_engines/template_url_prepopulate_data.cc b/chrome/browser/search_engines/template_url_prepopulate_data.cc
index 82da8f672b0ef4e46bef41667f94e0d11c05b77b..acd3089701c70accc981e12cdad80915b2971c9b 100644
--- a/chrome/browser/search_engines/template_url_prepopulate_data.cc
+++ b/chrome/browser/search_engines/template_url_prepopulate_data.cc
@@ -3364,8 +3364,8 @@ void GetPrepopulatedTemplateFromPrefs(Profile* profile,
 
   size_t num_engines = list->GetSize();
   for (size_t i = 0; i != num_engines; ++i) {
-    Value* val;
-    DictionaryValue* engine;
+    const Value* val;
+    const DictionaryValue* engine;
     if (list->GetDictionary(i, &engine) &&
         engine->Get("name", &val) && val->GetAsString(&name) &&
         engine->Get("keyword", &val) && val->GetAsString(&keyword) &&