Assert that |resource| is always non-null in requestPendingScript()

third_party/WebKit/Source/core/html/parser/HTMLParserScriptRunner.cpp

 /*
  * 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 562 matching lines @@
   DCHECK(pendingScript->resource());
 
   // "Add the element to the end of the list of scripts that will execute
   //  when the document has finished parsing associated with the Document
   //  of the parser that created the element."
   m_scriptsToExecuteAfterParsing.append(pendingScript);
 }
 
 PendingScript* HTMLParserScriptRunner::requestPendingScript(
     Element* element) const {
-  // This should correctly return 0 for empty or invalid srcValues.
   ScriptResource* resource = toScriptLoaderIfPossible(element)->resource();
-  if (!resource) {
-    DVLOG(1) << "Not implemented.";  // Dispatch error event.
-    return nullptr;
-  }
-
+  // Here |resource| should be non-null. If it were nullptr,
+  // ScriptLoader::fetchScript() should have returned false and
+  // thus the control shouldn't have reached here.
+  CHECK(resource);
   return PendingScript::create(element, resource);
 }
 
 // The initial steps for 'An end tag whose tag name is "script"'
 // https://html.spec.whatwg.org/#scriptEndTag
 void HTMLParserScriptRunner::processScriptElementInternal(
     Element* script,
     const TextPosition& scriptStartPosition) {
   DCHECK(m_document);
   DCHECK(!hasParserBlockingScript());
@@ skipping 78 matching lines @@
 
 DEFINE_TRACE(HTMLParserScriptRunner) {
   visitor->trace(m_document);
   visitor->trace(m_host);
   visitor->trace(m_parserBlockingScript);
   visitor->trace(m_scriptsToExecuteAfterParsing);
   PendingScriptClient::trace(visitor);
 }
 
 }  // namespace blink