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

Source/core/dom/custom/CustomElement.cpp

Index: Source/core/dom/custom/CustomElement.cpp
diff --git a/Source/core/dom/custom/CustomElement.cpp b/Source/core/dom/custom/CustomElement.cpp
index 81443a6c9fe2356d4b3c4ef14bd870419b4082ae..b54fd5b541bfe1c6ea21f4464c7968a41e3bca7e 100644
--- a/Source/core/dom/custom/CustomElement.cpp
+++ b/Source/core/dom/custom/CustomElement.cpp
@@ -71,7 +71,7 @@ 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());
@@ -85,8 +85,15 @@ bool CustomElement::isValidName(const AtomicString& name, NameSet validNames)
 #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;