Add a requestFullscreen variant with a default (prefixed) type

third_party/WebKit/Source/core/dom/Fullscreen.h

Index: third_party/WebKit/Source/core/dom/Fullscreen.h
diff --git a/third_party/WebKit/Source/core/dom/Fullscreen.h b/third_party/WebKit/Source/core/dom/Fullscreen.h
index f14a4b628374aa9fe36484277804bb323d3e62f7..a93806df06f2cf48317309277284fd6908d50385 100644
--- a/third_party/WebKit/Source/core/dom/Fullscreen.h
+++ b/third_party/WebKit/Source/core/dom/Fullscreen.h
@@ -63,14 +63,16 @@ class CORE_EXPORT Fullscreen final
   static Element* currentFullScreenElementForBindingFrom(Document&);
   static bool isCurrentFullScreenElement(const Element&);
 
-  enum RequestType {
+  enum class RequestType {
     // Element.requestFullscreen()
-    UnprefixedRequest,
+    Unprefixed,
     // Element.webkitRequestFullscreen()/webkitRequestFullScreen() and
     // HTMLVideoElement.webkitEnterFullscreen()/webkitEnterFullScreen()
-    PrefixedRequest,
+    Prefixed,
   };
 
+  static void requestFullscreen(Element&);
+
   // |forCrossProcessDescendant| is used in OOPIF scenarios and is set to
   // true when fullscreen is requested for an out-of-process descendant
   // element.