Implement the unprefixed the Fullscreen API

Source/core/dom/Element.cpp

Index: Source/core/dom/Element.cpp
diff --git a/Source/core/dom/Element.cpp b/Source/core/dom/Element.cpp
index d7b4a1239835cec7ba4f6b992c0368b535cda941..0baf74844ac7ee1a49c18c480cedb4623e900ef9 100644
--- a/Source/core/dom/Element.cpp
+++ b/Source/core/dom/Element.cpp
@@ -2687,6 +2687,11 @@ void Element::setFloatingPointAttribute(const QualifiedName& attributeName, doub
     setAttribute(attributeName, AtomicString::number(value));
 }
 
+void Element::requestFullscreen()
+{
+    FullscreenElementStack::from(document()).requestFullScreenForElement(*this, FullscreenElementStack::UnprefixedRequest);
+}
+
 void Element::webkitRequestFullscreen()
 {
     FullscreenElementStack::from(document()).requestFullScreenForElement(*this, FullscreenElementStack::PrefixedRequest);