Add "metered" flag to DHCP offer vendor info.

Bug: 6344821
Change-Id: Ic8cd235a1cbdd848ff839f6f0f03161de2090751

TetherController.cpp

@@ -134,15 +134,17 @@ int TetherController::startTethering(int num_addrs, struct in_addr* addrs) {
             close(pipefd[0]);
         }
 
-        int num_processed_args = 4 + (num_addrs/2) + 1; // 1 null for termination
+        int num_processed_args = 5 + (num_addrs/2) + 1; // 1 null for termination
         char **args = (char **)malloc(sizeof(char *) * num_processed_args);
         args[num_processed_args - 1] = NULL;
         args[0] = (char *)"/system/bin/dnsmasq";
         args[1] = (char *)"--no-daemon";
         args[2] = (char *)"--no-resolv";
         args[3] = (char *)"--no-poll";
+        // TODO: pipe through metered status from ConnService
+        args[4] = (char *)"--dhcp-option-force=43,ANDROID_METERED";
 
-        int nextArg = 4;
+        int nextArg = 5;
         for (int addrIndex=0; addrIndex < num_addrs;) {
             char *start = strdup(inet_ntoa(addrs[addrIndex++]));
             char *end = strdup(inet_ntoa(addrs[addrIndex++]));