Fix setting textContent to empty string

third_party/WebKit/Source/core/dom/Node.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All
  * rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  *
@@ skipping 1285 matching lines @@
       return;
     case kElementNode:
     case kDocumentFragmentNode: {
       // FIXME: Merge this logic into replaceChildrenWithText.
       ContainerNode* container = toContainerNode(this);
 
       // Note: This is an intentional optimization.
       // See crbug.com/352836 also.
       // No need to do anything if the text is identical.
       if (container->hasOneTextChild() &&
-          toText(container->firstChild())->data() == text)
+          toText(container->firstChild())->data() == text && !text.isEmpty())
         return;
 
       ChildListMutationScope mutation(*this);
       // Note: This API will not insert empty text nodes:
       // https://dom.spec.whatwg.org/#dom-node-textcontent
       if (text.isEmpty()) {
         container->removeChildren(DispatchSubtreeModifiedEvent);
       } else {
         container->removeChildren(OmitSubtreeModifiedEvent);
         container->appendChild(document().createTextNode(text),
@@ skipping 1150 matching lines @@
   if (node) {
     std::stringstream stream;
     node->printNodePathTo(stream);
     LOG(INFO) << stream.str();
   } else {
     LOG(INFO) << "Cannot showNodePath for <null>";
   }
 }
 
 #endif