Fix race between add_writing_stalled and destroy stream
diff --git a/src/core/transport/chttp2_transport.c b/src/core/transport/chttp2_transport.c
index 617d988..89e6487 100644
--- a/src/core/transport/chttp2_transport.c
+++ b/src/core/transport/chttp2_transport.c
@@ -598,7 +598,7 @@
static void unlock(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t) {
GPR_TIMER_BEGIN("unlock", 0);
if (!t->writing_active && !t->closed &&
- grpc_chttp2_unlocking_check_writes(&t->global, &t->writing,
+ grpc_chttp2_unlocking_check_writes(exec_ctx, &t->global, &t->writing,
t->parsing_active)) {
t->writing_active = 1;
REF_TRANSPORT(t, "writing");