Restrict PromiseRejectionEvents to their originating world

Source/core/events/PromiseRejectionEvent.h

Index: Source/core/events/PromiseRejectionEvent.h
diff --git a/Source/core/events/PromiseRejectionEvent.h b/Source/core/events/PromiseRejectionEvent.h
index c71f5dbe04b5598b4aa51faad2fd551469712fb3..258fd65e296be9f2c4082ffc08a3f968ec7ae978 100644
--- a/Source/core/events/PromiseRejectionEvent.h
+++ b/Source/core/events/PromiseRejectionEvent.h
@@ -5,6 +5,7 @@
 #ifndef PromiseRejectionEvent_h
 #define PromiseRejectionEvent_h
 
+#include "bindings/core/v8/DOMWrapperWorld.h"
 #include "bindings/core/v8/ScopedPersistent.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptState.h"
@@ -32,6 +33,10 @@ public:
 
     virtual const AtomicString& interfaceName() const override;
 
+    // PromiseRejectionEvents are similar to ErrorEvents in that they can't be
+    // observed across different worlds.
+    virtual bool canBeDispatchedInWorld(const DOMWrapperWorld&) const override;
+
     DECLARE_VIRTUAL_TRACE();
 
 private: