Let Node.textContent never throw

Source/core/html/forms/TextFieldInputType.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2011 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 386 matching lines @@
     if (!placeholder) {
         RefPtr<HTMLElement> newElement = HTMLDivElement::create(element().document());
         placeholder = newElement.get();
         placeholder->setPseudo(AtomicString("-webkit-input-placeholder", AtomicString::ConstructFromLiteral));
         placeholder->setAttribute(idAttr, ShadowElementNames::placeholder());
         Element* container = containerElement();
         Node* previous = container ? container : element().innerTextElement();
         previous->parentNode()->insertBefore(placeholder, previous->nextSibling());
         ASSERT_WITH_SECURITY_IMPLICATION(placeholder->parentNode() == previous->parentNode());
     }
-    placeholder->setTextContent(placeholderText, ASSERT_NO_EXCEPTION);
+    placeholder->setTextContent(placeholderText);
 }
 
 bool TextFieldInputType::appendFormData(FormDataList& list, bool multipart) const
 {
     InputType::appendFormData(list, multipart);
     const AtomicString& dirnameAttrValue = element().fastGetAttribute(dirnameAttr);
     if (!dirnameAttrValue.isNull())
         list.appendData(dirnameAttrValue, element().directionForFormData());
     return true;
 }
@@ skipping 64 matching lines @@
 {
     return !element().isDisabledOrReadOnly();
 }
 
 bool TextFieldInputType::shouldSpinButtonRespondToWheelEvents()
 {
     return shouldSpinButtonRespondToMouseEvents() && element().focused();
 }
 
 } // namespace WebCore