shill: wimax: Autoconnect only one service per WiMAX device.

BUG=chrome-os-partner:11162
TEST=unit tests

Change-Id: Ie7a67035f2410f13c25991c57a955b76b71d791e
Reviewed-on: https://gerrit.chromium.org/gerrit/27169
Commit-Ready: Darin Petkov <petkov@chromium.org>
Reviewed-by: Darin Petkov <petkov@chromium.org>
Tested-by: Darin Petkov <petkov@chromium.org>
diff --git a/wimax_provider.cc b/wimax_provider.cc
index 38eebe2..4a63679 100644
--- a/wimax_provider.cc
+++ b/wimax_provider.cc
@@ -212,7 +212,8 @@
   }
 }
 
-WiMaxRefPtr WiMaxProvider::SelectCarrier(const WiMaxServiceRefPtr &service) {
+WiMaxRefPtr WiMaxProvider::SelectCarrier(
+    const WiMaxServiceConstRefPtr &service) {
   SLOG(WiMax, 2) << __func__ << "(" << service->GetStorageIdentifier() << ")";
   if (devices_.empty()) {
     LOG(ERROR) << "No WiMAX devices available.";