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.
Change-Id: I13becdd133cccc912b542d48061fcfe9f566099a
diff --git a/common/constants.cc b/common/constants.cc
index 0ac22f3..324bdc5 100644
--- a/common/constants.cc
+++ b/common/constants.cc
@@ -93,5 +93,6 @@
const char kPayloadPropertyAuthorization[] = "AUTHORIZATION";
const char kPayloadPropertyUserAgent[] = "USER_AGENT";
const char kPayloadPropertyPowerwash[] = "POWERWASH";
+const char kPayloadPropertyNetworkId[] = "NETWORK_ID";
} // namespace chromeos_update_engine