Document attribute charset and its aliases to return UTF-8

Source/core/dom/Document.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 4199 matching lines @@
         && !ElementTraversal::firstWithin(*m_titleElement)
         && encoding() == Latin1Encoding()
         && m_titleElement->textContent().containsOnlyLatin1()) {
 
         CString originalBytes = m_titleElement->textContent().latin1();
         OwnPtr<TextCodec> codec = newTextCodec(newData.encoding());
         String correctlyDecodedTitle = codec->decode(originalBytes.data(), originalBytes.length(), DataEOF);
         m_titleElement->setTextContent(correctlyDecodedTitle);
     }
 
+    ASSERT(newData.encoding().isValid());
     m_encodingData = newData;
 
     // FIXME: Should be removed as part of https://code.google.com/p/chromium/issues/detail?id=319643
     bool shouldUseVisualOrdering = m_encodingData.encoding().usesVisualOrdering();
     if (shouldUseVisualOrdering != m_visuallyOrdered) {
         m_visuallyOrdered = shouldUseVisualOrdering;
         // FIXME: How is possible to not have a layoutObject here?
         if (layoutView())
             layoutView()->mutableStyleRef().setRTLOrdering(m_visuallyOrdered ? VisualOrder : LogicalOrder);
         setNeedsStyleRecalc(SubtreeStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::VisuallyOrdered));
@@ skipping 1508 matching lines @@
 #ifndef NDEBUG
 using namespace blink;
 void showLiveDocumentInstances()
 {
     WeakDocumentSet& set = liveDocumentSet();
     fprintf(stderr, "There are %u documents currently alive:\n", set.size());
     for (Document* document : set)
         fprintf(stderr, "- Document %p URL: %s\n", document, document->url().string().utf8().data());
 }
 #endif