Replace command.applyTo() with inlined builder operations

These are much easier to understand.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=137446273

javatests/google/registry/flows/host/testdata/host_update.xml

@@ -5,11 +5,11 @@
        xmlns:host="urn:ietf:params:xml:ns:host-1.0">
         <host:name>%OLD-HOSTNAME%</host:name>
         <host:add>
-          %ADD-HOSTADDRS%
+          %ADD-HOSTADDRSORSTATUS%
           <host:status s="clientUpdateProhibited"/>
         </host:add>
         <host:rem>
-          %REM-HOSTADDRS%
+          %REM-HOSTADDRSORSTATUS%
         </host:rem>
         <host:chg>
           <host:name>%NEW-HOSTNAME%</host:name>