Don't report promise rejection events during the microtask checkpoint

third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h

Index: third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h b/third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h
index 3cd5e06d40e98e029dded90d2f9fa3d00a2be830..3521d0461c0ee245565aec2dcc28ebef4ca51422 100644
--- a/third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h
+++ b/third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h
@@ -72,6 +72,11 @@ public:
         m_handle.SetWeak(parameters, callback, type);
     }
 
+    void clearWeak()
+    {
+        m_handle.template ClearWeak<void>();
+    }
+
     bool isEmpty() const { return m_handle.IsEmpty(); }
     bool isWeak() const { return m_handle.IsWeak(); }