Revert of Remove the allowfullscreen exemption for the video-specific fullscreen API

Source/core/dom/Fullscreen.cpp

Index: Source/core/dom/Fullscreen.cpp
diff --git a/Source/core/dom/Fullscreen.cpp b/Source/core/dom/Fullscreen.cpp
index 2b8c345c4e6655f50452be2e47f4f61283ef46a7..1385a62cb60efc64dacf574377346e9e1afc6960 100644
--- a/Source/core/dom/Fullscreen.cpp
+++ b/Source/core/dom/Fullscreen.cpp
@@ -77,7 +77,7 @@ static bool fullscreenElementReady(const Element& element, Fullscreen::RequestTy
 
     // |element|'s node document's fullscreen enabled flag is set.
     if (!fullscreenIsAllowedForAllOwners(element.document())) {
-        if (requestType == Fullscreen::InternalVideoRequest)
+        if (requestType == Fullscreen::PrefixedVideoRequest)
             UseCounter::count(element.document(), UseCounter::VideoFullscreenAllowedExemption);
         else
             return false;