Invalid chars should not be allowed as first character in custom element name

Source/core/dom/custom/CustomElement.cpp

 /*
  * Copyright (C) 2013 Google 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.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 53 matching lines @@
     if (isValidName(lower, EmbedderNames))
         return;
     embedderCustomElementNames().append(lower);
 }
 
 bool CustomElement::isValidName(const AtomicString& name, NameSet validNames)
 {
     if ((validNames & EmbedderNames) && kNotFound != embedderCustomElementNames().find(name))
         return Document::isValidName(name);
 
-    if ((validNames & StandardNames) && kNotFound != name.find('-')) {
+    if ((validNames & StandardNames) && kNotFound != name.find('-') && kNotFound == name.find(':')) {

[dglazkov, 2014/10/16 17:41:26]

This change is good.

         DEFINE_STATIC_LOCAL(Vector<AtomicString>, reservedNames, ());
         if (reservedNames.isEmpty()) {
             reservedNames.append(MathMLNames::annotation_xmlTag.localName());
 #if ENABLE(SVG_FONTS)
             reservedNames.append(SVGNames::font_faceTag.localName());
             reservedNames.append(SVGNames::font_face_srcTag.localName());
             reservedNames.append(SVGNames::font_face_uriTag.localName());
             reservedNames.append(SVGNames::font_face_formatTag.localName());
             reservedNames.append(SVGNames::font_face_nameTag.localName());
             reservedNames.append(SVGNames::missing_glyphTag.localName());
 #endif
         }
 
-        if (kNotFound == reservedNames.find(name))
+        if (kNotFound == reservedNames.find(name)) {
+            if (!name.string().is8Bit()) {
+                const UChar32 c = name.characters16()[0];
+                if (c == 0x0B83 || c == 0x0F88 || c == 0x0F89 || c == 0x0F8A || c == 0x0F8B)

[dglazkov, 2014/10/07 15:13:13]

This set of character comparisons seems out of place. Should it not be the same
as Document::isValidName?

There's a tricky balance between what spec says and what Blink implements in
Document::isValidName. Do you know if there's a difference there?

[dglazkov, 2014/10/16 17:41:26]

What I meant to say here is that you should not be stuffing character
comparisons into this function. This function just wants to call another
function that tells it whether the name is valid.

+                    return false;
+            }
+
             return Document::isValidName(name.string());
+        }
     }
 
     return false;
 }
 
 void CustomElement::define(Element* element, PassRefPtr<CustomElementDefinition> passDefinition)
 {
     RefPtr<CustomElementDefinition> definition(passDefinition);
 
     switch (element->customElementState()) {
@@ skipping 39 matching lines @@
         break;
 
     case Element::WaitingForUpgrade:
     case Element::Upgraded:
         CustomElementObserver::notifyElementWasDestroyed(element);
         break;
     }
 }
 
 } // namespace blink