Make gaia and oauth token fetchers recover from ERR_NETWORK_CHANGED.

google_apis/gaia/gaia_auth_fetcher.cc

Index: google_apis/gaia/gaia_auth_fetcher.cc
diff --git a/google_apis/gaia/gaia_auth_fetcher.cc b/google_apis/gaia/gaia_auth_fetcher.cc
index 853e6c9cd983b3f5bbd6dbc191b5ce423d356677..b4f7df6e73467ceed93913fde9993205a33e93ba 100644
--- a/google_apis/gaia/gaia_auth_fetcher.cc
+++ b/google_apis/gaia/gaia_auth_fetcher.cc
@@ -227,6 +227,12 @@ net::URLFetcher* GaiaAuthFetcher::CreateGaiaFetcher(
   // explicitly.
   to_return->SetLoadFlags(load_flags);
 
+  // Fetchers are sometimes cancelled because a network change was detected,
+  // especially at startup and after sign-in on ChromeOS. Retrying once should
+  // be enough in those cases; let the fetcher retry up to 3 times just in case.
+  // http://crbug.com/163710
+  to_return->SetAutomaticallyRetryOnNetworkChanges(3);
+
   if (!headers.empty())
     to_return->SetExtraRequestHeaders(headers);