Allow to set the network used for an update attempt.
When triggering an update attempt in Android, we can force all the
traffic to go through a given network by passing a NETWORK_ID=<id>
in the extra key-value pair field.
Bug: 29921093
TEST=Called update_engine_client passing NETWORK_ID.
(cherry picked from commit 87792ea818a63f2d246bbba2b7429b85ee8d669f)
Change-Id: I0e8a245961788c75106832e9fea8b07cd894f22d
diff --git a/common/constants.cc b/common/constants.cc
index fd2b542..c3556f8 100644
--- a/common/constants.cc
+++ b/common/constants.cc
@@ -92,5 +92,6 @@
const char kPayloadPropertyAuthorization[] = "AUTHORIZATION";
const char kPayloadPropertyUserAgent[] = "USER_AGENT";
const char kPayloadPropertyPowerwash[] = "POWERWASH";
+const char kPayloadPropertyNetworkId[] = "NETWORK_ID";
} // namespace chromeos_update_engine