PlzNavigate: properly execute BeforeUnload on renderer initiated navigations

components/test_runner/test_runner_for_specific_view.cc

Index: components/test_runner/test_runner_for_specific_view.cc
diff --git a/components/test_runner/test_runner_for_specific_view.cc b/components/test_runner/test_runner_for_specific_view.cc
index 75b8d0d0475439642e4ecaf5c7329df7e73ab5d7..30d5082a915b0131874a3a40f012c5aa81f87aa1 100644
--- a/components/test_runner/test_runner_for_specific_view.cc
+++ b/components/test_runner/test_runner_for_specific_view.cc
@@ -566,7 +566,13 @@ void TestRunnerForSpecificView::DidLosePointerLockInternal() {
 }
 
 bool TestRunnerForSpecificView::CallShouldCloseOnWebView() {
-  return web_view()->mainFrame()->dispatchBeforeUnloadEvent();
+  if (!web_view()->mainFrame()->toWebLocalFrame()) {
+    CHECK(false) << "This function cannot be called if the main frame is not a "
+                    "local frame.";
+  }
+
+  return web_view()->mainFrame()->toWebLocalFrame()->dispatchBeforeUnloadEvent(
+      false);
 }
 
 void TestRunnerForSpecificView::SetDomainRelaxationForbiddenForURLScheme(