Implement CustomElement::isValidName()

third_party/WebKit/Source/core/dom/custom/CustomElement.cpp

Index: third_party/WebKit/Source/core/dom/custom/CustomElement.cpp
diff --git a/third_party/WebKit/Source/core/dom/custom/CustomElement.cpp b/third_party/WebKit/Source/core/dom/custom/CustomElement.cpp
index 90569898c64ffbe0506a70a3a883229adfe56866..eebcb2d9f9ec13d9c35fa040d817c2d1195b30bb 100644
--- a/third_party/WebKit/Source/core/dom/custom/CustomElement.cpp
+++ b/third_party/WebKit/Source/core/dom/custom/CustomElement.cpp
@@ -5,9 +5,31 @@
 #include "core/dom/custom/CustomElement.h"
 
 #include "platform/text/Character.h"
+#include "wtf/text/AtomicStringHash.h"
 
 namespace blink {
 
+bool CustomElement::isValidName(const AtomicString& name)
+{
+    if (!isPotentialCustomElementName(name))
+        return false;
+
+    // https://html.spec.whatwg.org/multipage/scripting.html#valid-custom-element-name
+    DEFINE_STATIC_LOCAL(HashSet<AtomicString>, hyphenContainingElementNames, ());
+    if (hyphenContainingElementNames.isEmpty()) {
+        hyphenContainingElementNames.add("annotation-xml");
+        hyphenContainingElementNames.add("color-profile");
+        hyphenContainingElementNames.add("font-face");
+        hyphenContainingElementNames.add("font-face-src");
+        hyphenContainingElementNames.add("font-face-uri");
+        hyphenContainingElementNames.add("font-face-format");
+        hyphenContainingElementNames.add("font-face-name");
+        hyphenContainingElementNames.add("missing-glyph");
+    }
+
+    return !hyphenContainingElementNames.contains(name);
+}
+
 bool CustomElement::isPotentialCustomElementName(const AtomicString& name)
 {
     if (!name.length() || name[0] < 'a' || name[0] > 'z')