Revert "Revert "Proto API for LB request/responses""
diff --git a/gRPC.podspec b/gRPC.podspec
index 5b4d24e..05e3802 100644
--- a/gRPC.podspec
+++ b/gRPC.podspec
@@ -186,6 +186,7 @@
                       'src/core/client_config/client_config.h',
                       'src/core/client_config/connector.h',
                       'src/core/client_config/initial_connect_string.h',
+                      'src/core/client_config/lb_policies/load_balancer_api.h',
                       'src/core/client_config/lb_policies/pick_first.h',
                       'src/core/client_config/lb_policies/round_robin.h',
                       'src/core/client_config/lb_policy.h',
@@ -246,6 +247,7 @@
                       'src/core/json/json_common.h',
                       'src/core/json/json_reader.h',
                       'src/core/json/json_writer.h',
+                      'src/core/proto/grpc/lb/v0/load_balancer.pb.h',
                       'src/core/statistics/census_interface.h',
                       'src/core/statistics/census_rpc_stats.h',
                       'src/core/surface/api_trace.h',
@@ -287,6 +289,10 @@
                       'src/core/transport/transport_impl.h',
                       'src/core/census/aggregation.h',
                       'src/core/census/rpc_metric_id.h',
+                      'third_party/nanopb/pb.h',
+                      'third_party/nanopb/pb_common.h',
+                      'third_party/nanopb/pb_decode.h',
+                      'third_party/nanopb/pb_encode.h',
                       'include/grpc/grpc_security.h',
                       'include/grpc/impl/codegen/byte_buffer.h',
                       'include/grpc/impl/codegen/compression_types.h',
@@ -336,6 +342,7 @@
                       'src/core/client_config/connector.c',
                       'src/core/client_config/default_initial_connect_string.c',
                       'src/core/client_config/initial_connect_string.c',
+                      'src/core/client_config/lb_policies/load_balancer_api.c',
                       'src/core/client_config/lb_policies/pick_first.c',
                       'src/core/client_config/lb_policies/round_robin.c',
                       'src/core/client_config/lb_policy.c',
@@ -399,6 +406,7 @@
                       'src/core/json/json_reader.c',
                       'src/core/json/json_string.c',
                       'src/core/json/json_writer.c',
+                      'src/core/proto/grpc/lb/v0/load_balancer.pb.c',
                       'src/core/surface/alarm.c',
                       'src/core/surface/api_trace.c',
                       'src/core/surface/byte_buffer.c',
@@ -452,7 +460,10 @@
                       'src/core/census/initialize.c',
                       'src/core/census/operation.c',
                       'src/core/census/placeholders.c',
-                      'src/core/census/tracing.c'
+                      'src/core/census/tracing.c',
+                      'third_party/nanopb/pb_common.c',
+                      'third_party/nanopb/pb_decode.c',
+                      'third_party/nanopb/pb_encode.c'
 
     ss.private_header_files = 'src/core/profiling/timers.h',
                               'src/core/support/block_annotate.h',
@@ -492,6 +503,7 @@
                               'src/core/client_config/client_config.h',
                               'src/core/client_config/connector.h',
                               'src/core/client_config/initial_connect_string.h',
+                              'src/core/client_config/lb_policies/load_balancer_api.h',
                               'src/core/client_config/lb_policies/pick_first.h',
                               'src/core/client_config/lb_policies/round_robin.h',
                               'src/core/client_config/lb_policy.h',
@@ -552,6 +564,7 @@
                               'src/core/json/json_common.h',
                               'src/core/json/json_reader.h',
                               'src/core/json/json_writer.h',
+                              'src/core/proto/grpc/lb/v0/load_balancer.pb.h',
                               'src/core/statistics/census_interface.h',
                               'src/core/statistics/census_rpc_stats.h',
                               'src/core/surface/api_trace.h',
@@ -592,7 +605,11 @@
                               'src/core/transport/transport.h',
                               'src/core/transport/transport_impl.h',
                               'src/core/census/aggregation.h',
-                              'src/core/census/rpc_metric_id.h'
+                              'src/core/census/rpc_metric_id.h',
+                              'third_party/nanopb/pb.h',
+                              'third_party/nanopb/pb_common.h',
+                              'third_party/nanopb/pb_decode.h',
+                              'third_party/nanopb/pb_encode.h'
 
     ss.header_mappings_dir = '.'
     # This isn't officially supported in Cocoapods. We've asked for an alternative: