LibWeb: Switch IDL from UseNewAKString to UseDeprecatedAKString

NewAKString is effectively the default for any new IDL interface, so
let's mark this as the default behavior. It also makes it much easier to
figure out whatever interfaces are still left to port over to new AK
String.

Userland/Libraries/LibWeb/CSS/CSSConditionRule.idl

@@ -1,6 +1,6 @@
 #import <CSS/CSSGroupingRule.idl>
 
-[Exposed=Window, UseNewAKString]
+[Exposed=Window]
 interface CSSConditionRule : CSSGroupingRule {
     attribute CSSOMString conditionText;
 };

Userland/Libraries/LibWeb/CSS/CSSKeyframeRule.idl

@@ -1,6 +1,6 @@
 #import <CSS/CSSRule.idl>
 
-[Exposed=Window, UseNewAKString]
+[Exposed=Window]
 interface CSSKeyframeRule : CSSRule {
     attribute CSSOMString keyText;
     [SameObject, PutForwards=cssText] readonly attribute CSSStyleDeclaration style;

Userland/Libraries/LibWeb/CSS/CSSKeyframesRule.idl

@@ -1,6 +1,6 @@
 #import <CSS/CSSRule.idl>
 
-[Exposed=Window, UseNewAKString]
+[Exposed=Window]
 interface CSSKeyframesRule : CSSRule {
     attribute CSSOMString name;
     readonly attribute unsigned long length;

Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.idl

@@ -1,5 +1,5 @@
 // https://drafts.csswg.org/cssom/#cssstyledeclaration
-[Exposed=Window]
+[Exposed=Window, UseDeprecatedAKString]
 interface CSSStyleDeclaration {
 
     [CEReactions] attribute CSSOMString cssText;

Userland/Libraries/LibWeb/CSS/MediaList.idl

@@ -1,4 +1,4 @@
-[Exposed=Window, UseNewAKString]
+[Exposed=Window]
 interface MediaList {
     [LegacyNullToEmptyString] stringifier attribute CSSOMString mediaText;
     readonly attribute unsigned long length;

Userland/Libraries/LibWeb/CSS/MediaQueryListEvent.idl

@@ -1,7 +1,7 @@
 #import <DOM/Event.idl>
 
 // https://w3c.github.io/csswg-drafts/cssom-view-1/#mediaquerylistevent
-[Exposed=Window, UseNewAKString]
+[Exposed=Window]
 interface MediaQueryListEvent : Event {
     constructor(CSSOMString type, optional MediaQueryListEventInit eventInitDict = {});
 

Userland/Libraries/LibWeb/CSS/StyleSheet.idl

@@ -3,7 +3,7 @@
 #import <DOM/Element.idl>
 
 // https://drafts.csswg.org/cssom/#stylesheet
-[Exposed=Window]
+[Exposed=Window, UseDeprecatedAKString]
 interface StyleSheet {
 
     readonly attribute Element? ownerNode;