Support type selector for camel-cased SVG elements in HTML.

Source/core/css/SelectorFilter.cpp

Index: Source/core/css/SelectorFilter.cpp
diff --git a/Source/core/css/SelectorFilter.cpp b/Source/core/css/SelectorFilter.cpp
index 42d4e3fd28cf558ab50cb26974734b93df647d15..0c9f7935c796f36528d9ddafc371b7540aa78588 100644
--- a/Source/core/css/SelectorFilter.cpp
+++ b/Source/core/css/SelectorFilter.cpp
@@ -30,6 +30,7 @@
 #include "core/css/SelectorFilter.h"
 
 #include "core/css/CSSSelector.h"
+#include "core/dom/Document.h"
 
 namespace blink {
 
@@ -38,7 +39,10 @@ enum { TagNameSalt = 13, IdAttributeSalt = 17, ClassAttributeSalt = 19 };
 
 static inline void collectElementIdentifierHashes(const Element& element, Vector<unsigned, 4>& identifierHashes)
 {
-    identifierHashes.append(element.localName().impl()->existingHash() * TagNameSalt);
+    AtomicString localName = element.localName();
+    if (!element.isHTMLElement() && element.document().isHTMLDocument())
+        localName = localName.lower();
+    identifierHashes.append(localName.impl()->existingHash() * TagNameSalt);
     if (element.hasID())
         identifierHashes.append(element.idForStyleResolution().impl()->existingHash() * IdAttributeSalt);
     if (element.isStyledElement() && element.hasClass()) {