Remove the HTMLVideoElement-specific prefixed fullscreen API

Source/core/html/HTMLMediaElement.cpp

Index: Source/core/html/HTMLMediaElement.cpp
diff --git a/Source/core/html/HTMLMediaElement.cpp b/Source/core/html/HTMLMediaElement.cpp
index cec3e8f28f9a7b68d9fdd7a07390770f9473bf65..00dd8693be3b35898ee12af2129452a5aa5ca0e7 100644
--- a/Source/core/html/HTMLMediaElement.cpp
+++ b/Source/core/html/HTMLMediaElement.cpp
@@ -317,8 +317,6 @@ HTMLMediaElement::HTMLMediaElement(const QualifiedName& tagName, Document& docum
     if (document.settings()) {
         if (document.settings()->mediaPlaybackRequiresUserGesture())
             addBehaviorRestriction(RequireUserGestureForPlayRestriction);
-        if (document.settings()->mediaFullscreenRequiresUserGesture())
-            addBehaviorRestriction(RequireUserGestureForFullscreenRestriction);
     }
 
     // We must always have a ShadowRoot so children like <source> will not render
@@ -3457,14 +3455,6 @@ void HTMLMediaElement::enterFullscreen()
         FullscreenElementStack::from(document()).requestFullScreenForElement(this, 0, FullscreenElementStack::ExemptIFrameAllowFullScreenRequirement);
 }
 
-void HTMLMediaElement::exitFullscreen()
-{
-    WTF_LOG(Media, "HTMLMediaElement::exitFullscreen");
-
-    if (document().settings() && document().settings()->fullScreenEnabled() && isFullscreen())
-        FullscreenElementStack::from(document()).webkitCancelFullScreen();
-}
-
 void HTMLMediaElement::didBecomeFullscreenElement()
 {
     if (hasMediaControls())