Only populate line number in case parsing synchronously.

Source/core/dom/ScriptableDocumentParser.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 27 matching lines @@
     // JavaScript document.open() call right now, or it should be ignored.
     virtual bool isExecutingScript() const { return false; }
 
     // FIXME: Only the HTMLDocumentParser ever blocks script execution on
     // stylesheet load, which is likely a bug in the XMLDocumentParser.
     virtual void executeScriptsWaitingForResources() { }
 
     virtual bool isWaitingForScripts() const = 0;
 
     // These are used to expose the current line/column to the scripting system.
+    virtual bool hasLineNumber() const = 0;

[rmcilroy, 2014/12/12 14:18:31]

Maybe isParsingAtLineNumber or similar to be explicit that this means that the
current line number is something we are currently dealing with?

[pfeldman, 2014/12/12 17:21:06]

Done.

     virtual OrdinalNumber lineNumber() const = 0;
     virtual TextPosition textPosition() const = 0;
 
     void setWasCreatedByScript(bool wasCreatedByScript) { m_wasCreatedByScript = wasCreatedByScript; }
     bool wasCreatedByScript() const { return m_wasCreatedByScript; }
 
     ParserContentPolicy parserContentPolicy() { return m_parserContentPolicy; }
 
 protected:
     explicit ScriptableDocumentParser(Document&, ParserContentPolicy = AllowScriptingContent);
 
 private:
     virtual ScriptableDocumentParser* asScriptableDocumentParser() override final { return this; }
 
     // http://www.whatwg.org/specs/web-apps/current-work/#script-created-parser
     bool m_wasCreatedByScript;
     ParserContentPolicy m_parserContentPolicy;
 };
 
 }
 
 #endif // ScriptableDocumentParser_h