Fix Memory Leak. Ensure secure_endpoint is destructed correctly.

PiperOrigin-RevId: 660069837

src/core/handshaker/security/secure_endpoint.cc

@@ -108,7 +108,6 @@ struct secure_endpoint : public grpc_endpoint {
   }
 
   ~secure_endpoint() {
-    memory_owner.Reset();
     tsi_frame_protector_destroy(protector);
     tsi_zero_copy_grpc_protector_destroy(zero_copy_protector);
     grpc_slice_buffer_destroy(&source_buffer);
@@ -380,9 +379,12 @@ static void flush_write_staging_buffer(secure_endpoint* ep, uint8_t** cur,
 
 static void on_write(void* user_data, grpc_error_handle error) {
   secure_endpoint* ep = static_cast<secure_endpoint*>(user_data);
-  grpc_core::ExecCtx::Run(DEBUG_LOCATION, std::exchange(ep->write_cb, nullptr),
-                          std::move(error));
+  grpc_closure* cb = ep->write_cb;
+  ep->write_cb = nullptr;
   SECURE_ENDPOINT_UNREF(ep, "write");
+  grpc_core::EnsureRunInExecCtx([cb, error = std::move(error)]() {
+    grpc_core::Closure::Run(DEBUG_LOCATION, cb, error);
+  });
 }
 
 static void endpoint_write(grpc_endpoint* secure_ep, grpc_slice_buffer* slices,
@@ -505,6 +507,7 @@ static void endpoint_write(grpc_endpoint* secure_ep, grpc_slice_buffer* slices,
 static void endpoint_destroy(grpc_endpoint* secure_ep) {
   secure_endpoint* ep = reinterpret_cast<secure_endpoint*>(secure_ep);
   ep->wrapped_ep.reset();
+  ep->memory_owner.Reset();
   SECURE_ENDPOINT_UNREF(ep, "destroy");
 }