outlier detection LB: don't include channel args in subchannel map key (#30158)

BUILD

@@ -4389,6 +4389,7 @@ grpc_cc_library(
         "ref_counted",
         "ref_counted_ptr",
         "server_address",
+        "sockaddr_utils",
     ],
 )
 

src/core/ext/filters/client_channel/lb_policy/outlier_detection/outlier_detection.cc

@@ -48,6 +48,7 @@
 #include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 #include "src/core/ext/filters/client_channel/lb_policy_registry.h"
 #include "src/core/ext/filters/client_channel/subchannel_interface.h"
+#include "src/core/lib/address_utils/sockaddr_utils.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/debug/trace.h"
 #include "src/core/lib/gpr/env.h"
@@ -554,10 +555,9 @@ OutlierDetectionLb::~OutlierDetectionLb() {
 
 std::string OutlierDetectionLb::MakeKeyForAddress(
     const ServerAddress& address) {
-  // Strip off attributes to construct the key.
-  return ServerAddress(address.address(),
-                       grpc_channel_args_copy(address.args()))
-      .ToString();
+  // Use only the address, not the attributes.
+  auto addr_str = grpc_sockaddr_to_string(&address.address(), false);
+  return addr_str.ok() ? addr_str.value() : addr_str.status().ToString();
 }
 
 void OutlierDetectionLb::ShutdownLocked() {