components: Change auto to not deduce raw pointers.

components/ntp_snippets/ntp_snippets_fetcher.cc

Index: components/ntp_snippets/ntp_snippets_fetcher.cc
diff --git a/components/ntp_snippets/ntp_snippets_fetcher.cc b/components/ntp_snippets/ntp_snippets_fetcher.cc
index d0cb31ecac21dc1e117ccd277679ec8bead4aab7..bc5dd91c6542e7e70bdf3b86dd442f5678a8fd19 100644
--- a/components/ntp_snippets/ntp_snippets_fetcher.cc
+++ b/components/ntp_snippets/ntp_snippets_fetcher.cc
@@ -261,7 +261,7 @@ std::string NTPSnippetsFetcher::RequestParams::BuildRequest() {
                                only_return_personalized_results);
 
     auto content_restricts = base::MakeUnique<base::ListValue>();
-    for (const auto& metadata : {"TITLE", "SNIPPET", "THUMBNAIL"}) {
+    for (const auto* metadata : {"TITLE", "SNIPPET", "THUMBNAIL"}) {
       auto entry = base::MakeUnique<base::DictionaryValue>();
       entry->SetString("type", "METADATA");
       entry->SetString("value", metadata);