[Cleanup] Remove StringPrintf from global namespace

google_apis/gaia/oauth2_access_token_fetcher.cc

Index: google_apis/gaia/oauth2_access_token_fetcher.cc
diff --git a/google_apis/gaia/oauth2_access_token_fetcher.cc b/google_apis/gaia/oauth2_access_token_fetcher.cc
index 0cd4456537cb6199a9ca1268ac291257f3ff3bd7..edefa7e33bde8b26e7ddd97e6280bcd6b6667ef4 100644
--- a/google_apis/gaia/oauth2_access_token_fetcher.cc
+++ b/google_apis/gaia/oauth2_access_token_fetcher.cc
@@ -188,14 +188,14 @@ std::string OAuth2AccessTokenFetcher::MakeGetAccessTokenBody(
   std::string enc_refresh_token =
       net::EscapeUrlEncodedData(refresh_token, true);
   if (scopes.empty()) {
-    return StringPrintf(
+    return base::StringPrintf(
         kGetAccessTokenBodyFormat,
         enc_client_id.c_str(),
         enc_client_secret.c_str(),
         enc_refresh_token.c_str());
   } else {
     std::string scopes_string = JoinString(scopes, ' ');
-    return StringPrintf(
+    return base::StringPrintf(
         kGetAccessTokenBodyWithScopeFormat,
         enc_client_id.c_str(),
         enc_client_secret.c_str(),