Missing document null pointer check in Internals.

third_party/WebKit/Source/core/testing/Internals.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  * Copyright (C) 2013 Apple 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.
@@ skipping 2275 matching lines @@
   }
 
   FrameView* frameView = document->view();
   frameView->updateAllLifecyclePhases();
   frameView->setTracksPaintInvalidations(false);
 }
 
 void Internals::updateLayoutIgnorePendingStylesheetsAndRunPostLayoutTasks(
     Node* node,
     ExceptionState& exceptionState) {
-  Document* document;
+  Document* document = nullptr;
   if (!node) {
     document = contextDocument();
   } else if (node->isDocumentNode()) {
     document = toDocument(node);
   } else if (isHTMLIFrameElement(*node)) {
     document = toHTMLIFrameElement(*node).contentDocument();
-  } else {
+  }
+
+  if (!document) {
     exceptionState.throwTypeError(
         "The node provided is neither a document nor an IFrame.");
     return;
   }
   document->updateStyleAndLayoutIgnorePendingStylesheets(
       Document::RunPostLayoutTasksSynchronously);
 }
 
 void Internals::forceFullRepaint(Document* document,
                                  ExceptionState& exceptionState) {
@@ skipping 695 matching lines @@
     return ClientRect::create();
 
   return ClientRect::create(FloatRect(node->layoutObject()->visualRect()));
 }
 
 void Internals::crash() {
   CHECK(false) << "Intentional crash";
 }
 
 }  // namespace blink