Check that PendingScript::m_streamer is always null when resource() is null

third_party/WebKit/Source/core/dom/PendingScript.h

 /*
  * Copyright (C) 2010 Google, Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 95 matching lines @@
 
   void dispose();
 
  private:
   PendingScript(Element*,
                 ScriptResource*,
                 const TextPosition&,
                 bool isForTesting = false);
   PendingScript() = delete;
 
+  void checkState() const;
+
   // ScriptResourceClient
   void notifyFinished(Resource*) override;
   String debugName() const override { return "PendingScript"; }
   void notifyAppendData(ScriptResource*) override;
 
   // MemoryCoordinatorClient
   void onPurgeMemory() override;
 
   bool m_watchingForLoad;
 
   // |m_element| must points to the corresponding ScriptLoader's element and
   // thus must be non-null before dispose() is called (except for unit tests).
   Member<Element> m_element;
 
   TextPosition m_startingPosition;  // Only used for inline script tags.
   bool m_integrityFailure;
   double m_parserBlockingLoadStartTime;
 
   Member<ScriptStreamer> m_streamer;
   Member<PendingScriptClient> m_client;
 
   // This flag is used to skip non-null checks of |m_element| in unit tests,
   // because |m_element| can be null in unit tests.
   const bool m_isForTesting;
 };
 
 }  // namespace blink
 
 #endif  // PendingScript_h