Adds some code to help isolate where crash is happening

third_party/mojo/src/mojo/edk/js/drain_data.cc

Index: third_party/mojo/src/mojo/edk/js/drain_data.cc
diff --git a/third_party/mojo/src/mojo/edk/js/drain_data.cc b/third_party/mojo/src/mojo/edk/js/drain_data.cc
index 0667c64ca1b3b798af91d958b6aca8c58ee8501d..aa2f53221c36e8dd2dcc44e1bfe2cf0d375c81d8 100644
--- a/third_party/mojo/src/mojo/edk/js/drain_data.cc
+++ b/third_party/mojo/src/mojo/edk/js/drain_data.cc
@@ -42,11 +42,8 @@ DrainData::~DrainData() {
 
 void DrainData::WaitForData() {
   wait_id_ = Environment::GetDefaultAsyncWaiter()->AsyncWait(
-      handle_.get().value(),
-      MOJO_HANDLE_SIGNAL_READABLE,
-      MOJO_DEADLINE_INDEFINITE,
-      &DrainData::WaitCompleted,
-      this);
+      2, handle_.get().value(), MOJO_HANDLE_SIGNAL_READABLE,
+      MOJO_DEADLINE_INDEFINITE, &DrainData::WaitCompleted, this);
 }
 
 void DrainData::DataReady(MojoResult result) {