LibWeb/DOM: Stub out Element.requestPointerLock()

Does just enough to make classic.minecraft.net load and let you play.
Without actual pointer lock it's quite awkward though.

Author: AtkinsSJ

Libraries/LibWeb/DOM/Element.cpp

@@ -4338,6 +4338,15 @@ double Element::ensure_css_random_base_value(CSS::RandomCachingKey const& random
     });
 }
 
+GC::Ref<WebIDL::Promise> Element::request_pointer_lock(Optional<PointerLockOptions>)
+{
+    dbgln("FIXME: request_pointer_lock()");
+    auto promise = WebIDL::create_promise(realm());
+    auto error = WebIDL::NotSupportedError::create(realm(), "request_pointer_lock() is not implemented"_utf16);
+    WebIDL::reject_promise(realm(), promise, error);
+    return promise;
+}
+
 // The element to inherit style from.
 // If a pseudo-element is specified, this will return the element itself.
 // Otherwise, if this element is slotted somewhere, it will return the slot's element to inherit style from.

Libraries/LibWeb/DOM/Element.h

@@ -103,6 +103,11 @@ enum class ProximityToTheViewport : u8 {
     NotDetermined,
 };
 
+// https://w3c.github.io/pointerlock/#pointerlockoptions-dictionary
+struct PointerLockOptions {
+    bool unadjusted_movement = false;
+};
+
 class WEB_API Element
     : public ParentNode
     , public ChildNode<Element>
@@ -523,6 +528,8 @@ class WEB_API Element
 
     double ensure_css_random_base_value(CSS::RandomCachingKey const&);
 
+    GC::Ref<WebIDL::Promise> request_pointer_lock(Optional<PointerLockOptions>);
+
 protected:
     Element(Document&, DOM::QualifiedName);
     virtual void initialize(JS::Realm&) override;

Libraries/LibWeb/DOM/Element.idl

@@ -36,6 +36,11 @@ dictionary CheckVisibilityOptions {
     boolean visibilityProperty = false;
 };
 
+// https://w3c.github.io/pointerlock/#pointerlockoptions-dictionary
+dictionary PointerLockOptions {
+    boolean unadjustedMovement = false;
+};
+
 // https://dom.spec.whatwg.org/#element
 [Exposed=Window]
 interface Element : Node {
@@ -126,6 +131,9 @@ interface Element : Node {
 
     // https://drafts.csswg.org/css-shadow-parts/#idl
     [SameObject, PutForwards=value, ImplementedAs=part_list] readonly attribute DOMTokenList part;
+    
+    // https://w3c.github.io/pointerlock/#requestPointerLock
+    Promise<undefined> requestPointerLock(optional PointerLockOptions options = {});
 };
 
 dictionary GetHTMLOptions {