Fix objective c unit test and debugging functions

src/core/lib/transport/transport_op_string.cc

@@ -48,7 +48,13 @@ static void put_metadata_list(gpr_strvec* b, grpc_metadata_batch md) {
   grpc_linked_mdelem* m;
   for (m = md.list.head; m != nullptr; m = m->next) {
     if (m != md.list.head) gpr_strvec_add(b, gpr_strdup(", "));
-    put_metadata(b, m->md);
+    if (is_valid_mdelem_index(m->md_index)) {
+      char* tmp;
+      gpr_asprintf(&tmp, "index=%d" , m->md_index);
+      gpr_strvec_add(b, gpr_strdup("index="));
+    } else {
+      put_metadata(b, m->md);
+    }
   }
   if (md.deadline != GRPC_MILLIS_INF_FUTURE) {
     char* tmp;

src/objective-c/tests/CronetUnitTests/CronetUnitTests.m

@@ -140,11 +140,11 @@ grpc_channel_args *add_disable_client_authority_filter_args(grpc_channel_args *a
   grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
                               grpc_slice_from_static_string("val1"),
                               0,
-                              {{NULL, NULL, NULL, NULL}}},
+                              {0, {NULL, NULL, NULL, NULL}}},
                              {grpc_slice_from_static_string("key2"),
                               grpc_slice_from_static_string("val2"),
                               0,
-                              {{NULL, NULL, NULL, NULL}}}};
+                              {0, {NULL, NULL, NULL, NULL}}}};
 
   int port = grpc_pick_unused_port_or_die();
   char *addr;
@@ -274,11 +274,11 @@ grpc_channel_args *add_disable_client_authority_filter_args(grpc_channel_args *a
   grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
                               grpc_slice_from_static_string("val1"),
                               0,
-                              {{NULL, NULL, NULL, NULL}}},
+                              {0, {NULL, NULL, NULL, NULL}}},
                              {grpc_slice_from_static_string("key2"),
                               grpc_slice_from_static_string("val2"),
                               0,
-                              {{NULL, NULL, NULL, NULL}}}};
+                              {0, {NULL, NULL, NULL, NULL}}}};
 
   int port = grpc_pick_unused_port_or_die();
   char *addr;