Make CustomEvent::getEventInfo() pure virtual

Author: mar-cf

src/workerd/io/worker-interface.h

@@ -132,10 +132,8 @@ class WorkerInterface: public kj::HttpService {
     virtual uint16_t getType() = 0;
 
     // Get event info for tracing.
-    // Return none if this event type doesn't need tracing.
-    virtual kj::Maybe<tracing::EventInfo> getEventInfo() const {
-      return kj::none;
-    }
+    // Return kj::none if this event type doesn't need tracing.
+    virtual kj::Maybe<tracing::EventInfo> getEventInfo() const = 0;
 
     // If the CustomEvent fails before any of the other methods are called, this may be invoked
     // to report the failure reason.