Merge pull request #8765 from jtattermusch/fix_unreacheable_code_usage

Fix usage of GPR_UNREACHABLE_CODE

src/core/ext/lb_policy/pick_first/pick_first.c

@@ -293,7 +293,7 @@ static void pf_connectivity_changed(grpc_exec_ctx *exec_ctx, void *arg,
   loop:
     switch (p->checking_connectivity) {
       case GRPC_CHANNEL_INIT:
-        GPR_UNREACHABLE_CODE();
+        GPR_UNREACHABLE_CODE(return );
       case GRPC_CHANNEL_READY:
         grpc_connectivity_state_set(exec_ctx, &p->state_tracker,
                                     GRPC_CHANNEL_READY, GRPC_ERROR_NONE,

src/core/ext/lb_policy/round_robin/round_robin.c

@@ -553,7 +553,7 @@ static void rr_connectivity_changed(grpc_exec_ctx *exec_ctx, void *arg,
   }
   switch (sd->curr_connectivity_state) {
     case GRPC_CHANNEL_INIT:
-      GPR_UNREACHABLE_CODE();
+      GPR_UNREACHABLE_CODE(return );
     case GRPC_CHANNEL_READY:
       /* add the newly connected subchannel to the list of connected ones.
        * Note that it goes to the "end of the line". */