LibWeb/DOM: Stop including Element.h from AbstractElement.h

We only need the forward declaration here, and this will let us include
AbstractElement from Element.

Libraries/LibWeb/CSS/CSSDescriptors.cpp

@@ -9,6 +9,7 @@
 #include <LibWeb/CSS/Serialize.h>
 #include <LibWeb/CSS/StyleValues/StyleValueList.h>
 #include <LibWeb/Infra/Strings.h>
+#include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::CSS {
 

Libraries/LibWeb/CSS/CSSFontFaceDescriptors.cpp

@@ -5,7 +5,9 @@
  */
 
 #include <LibWeb/Bindings/CSSFontFaceDescriptorsPrototype.h>
+#include <LibWeb/Bindings/Intrinsics.h>
 #include <LibWeb/CSS/CSSFontFaceDescriptors.h>
+#include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::CSS {
 

Libraries/LibWeb/CSS/CSSPageDescriptors.cpp

@@ -5,7 +5,9 @@
  */
 
 #include <LibWeb/Bindings/CSSPageDescriptorsPrototype.h>
+#include <LibWeb/Bindings/Intrinsics.h>
 #include <LibWeb/CSS/CSSPageDescriptors.h>
+#include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::CSS {
 

Libraries/LibWeb/CSS/CSSStyleProperties.h

@@ -9,6 +9,7 @@
 
 #include <LibWeb/CSS/CSSStyleDeclaration.h>
 #include <LibWeb/CSS/GeneratedCSSStyleProperties.h>
+#include <LibWeb/DOM/Node.h>
 
 namespace Web::CSS {
 

Libraries/LibWeb/DOM/AbstractElement.cpp

@@ -5,6 +5,7 @@
  */
 
 #include <LibWeb/DOM/AbstractElement.h>
+#include <LibWeb/DOM/Element.h>
 
 namespace Web::DOM {
 

Libraries/LibWeb/DOM/AbstractElement.h

@@ -8,7 +8,7 @@
 
 #include <LibGC/Cell.h>
 #include <LibWeb/CSS/Selector.h>
-#include <LibWeb/DOM/Element.h>
+#include <LibWeb/Forward.h>
 
 namespace Web::DOM {
 

Libraries/LibWeb/Forward.h

@@ -185,6 +185,7 @@ class ConicGradientStyleValue;
 class ContentStyleValue;
 class CounterDefinitionsStyleValue;
 class CounterStyleValue;
+class CountersSet;
 class CSSAnimation;
 class CSSColorValue;
 class CSSConditionRule;