Internals.setValueForUser(): add argument type check.

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 2746 matching lines @@
                                               long) {
   return ScriptPromise::cast(scriptState,
                              v8String(scriptState->isolate(), "done"));
 }
 
 DEFINE_TRACE(Internals) {
   visitor->trace(m_runtimeFlags);
   ContextLifecycleObserver::trace(visitor);
 }
 
-void Internals::setValueForUser(Element* element, const String& value) {
-  toHTMLInputElement(element)->setValueForUser(value);
+void Internals::setValueForUser(HTMLInputElement* element,
+                                const String& value) {
+  element->setValueForUser(value);
 }
 
 String Internals::textSurroundingNode(Node* node,
                                       int x,
                                       int y,
                                       unsigned long maxLength) {
   if (!node)
     return String();
 
   // VisiblePosition and SurroundingText must be created with clean layout.
@@ skipping 256 matching lines @@
     return ClientRect::create();
 
   return ClientRect::create(FloatRect(node->layoutObject()->visualRect()));
 }
 
 void Internals::crash() {
   CHECK(false) << "Intentional crash";
 }
 
 }  // namespace blink