LibWeb: Move containment checks to Layout::Node

It fits better there and avoids having to reach into the Element
all the time.

Libraries/LibWeb/Layout/Node.cpp

@@ -98,11 +98,8 @@ bool Node::can_contain_boxes_with_position_absolute() const
     //    containing block.
     // 4. The paint containment box establishes an absolute positioning containing block and a fixed positioning
     //    containing block.
-    if (dom_node() && dom_node()->is_element()) {
-        auto element = as<DOM::Element>(dom_node());
-        if (element->has_layout_containment() || element->has_paint_containment())
-            return true;
-    }
+    if (has_layout_containment() || has_paint_containment())
+        return true;
 
     return false;
 }
@@ -244,11 +241,8 @@ bool Node::establishes_stacking_context() const
     // https://drafts.csswg.org/css-contain-2/#containment-types
     // 5. The layout containment box creates a stacking context.
     // 3. The paint containment box creates a stacking context.
-    if (dom_node() && dom_node()->is_element()) {
-        auto element = as<DOM::Element>(dom_node());
-        if (element->has_layout_containment() || element->has_paint_containment())
-            return true;
-    }
+    if (has_layout_containment() || has_paint_containment())
+        return true;
 
     // https://drafts.fxtf.org/compositing/#mix-blend-mode
     // Applying a blendmode other than normal to the element must establish a new stacking context.
@@ -959,6 +953,7 @@ void NodeWithStyle::apply_style(CSS::ComputedProperties const& computed_style)
     computed_values.set_isolation(computed_style.isolation());
     computed_values.set_mix_blend_mode(computed_style.mix_blend_mode());
     computed_values.set_view_transition_name(computed_style.view_transition_name());
+    computed_values.set_contain(computed_style.contain());
 
     computed_values.set_caret_color(computed_style.caret_color(*this));
 
@@ -1240,6 +1235,126 @@ CSS::UserSelect Node::user_select_used_value() const
     return computed_value;
 }
 
+// https://drafts.csswg.org/css-contain-2/#containment-size
+bool Node::has_size_containment() const
+{
+    // However, giving an element size containment has no effect if any of the following are true:
+
+    // - if the element does not generate a principal box (as is the case with 'display: contents' or 'display: none')
+    // Note: This is the principal box
+
+    // - if its inner display type is 'table'
+    if (display().is_table_inside())
+        return false;
+
+    // - if its principal box is an internal table box
+    if (display().is_internal_table())
+        return false;
+
+    // - if its principal box is an internal ruby box or a non-atomic inline-level box
+    // FIXME: Implement this.
+
+    if (computed_values().contain().size_containment)
+        return true;
+
+    return false;
+}
+// https://drafts.csswg.org/css-contain-2/#containment-inline-size
+bool Node::has_inline_size_containment() const
+{
+    // Giving an element inline-size containment has no effect if any of the following are true:
+
+    // - if the element does not generate a principal box (as is the case with 'display: contents' or 'display: none')
+    // Note: This is the principal box
+
+    // - if its inner display type is 'table'
+    if (display().is_table_inside())
+        return false;
+
+    // - if its principal box is an internal table box
+    if (display().is_internal_table())
+        return false;
+
+    // - if its principal box is an internal ruby box or a non-atomic inline-level box
+    // FIXME: Implement this.
+
+    if (computed_values().contain().inline_size_containment)
+        return true;
+
+    return false;
+}
+// https://drafts.csswg.org/css-contain-2/#containment-layout
+bool Node::has_layout_containment() const
+{
+    // However, giving an element layout containment has no effect if any of the following are true:
+
+    // - if the element does not generate a principal box (as is the case with 'display: contents' or 'display: none')
+    // Note: This is the principal box
+
+    // - if its principal box is an internal table box other than 'table-cell'
+    if (display().is_internal_table() && !display().is_table_cell())
+        return false;
+
+    // - if its principal box is an internal ruby box or a non-atomic inline-level box
+    // FIXME: Implement this.
+
+    if (computed_values().contain().layout_containment)
+        return true;
+
+    // https://drafts.csswg.org/css-contain-2/#valdef-content-visibility-auto
+    // Changes the used value of the 'contain' property so as to turn on layout containment, style containment, and
+    // paint containment for the element.
+    if (computed_values().content_visibility() == CSS::ContentVisibility::Auto)
+        return true;
+
+    return false;
+}
+// https://drafts.csswg.org/css-contain-2/#containment-style
+bool Node::has_style_containment() const
+{
+    // However, giving an element style containment has no effect if any of the following are true:
+
+    // - if the element does not generate a principal box (as is the case with 'display: contents' or 'display: none')
+    // Note: This is the principal box
+
+    if (computed_values().contain().style_containment)
+        return true;
+
+    // https://drafts.csswg.org/css-contain-2/#valdef-content-visibility-auto
+    // Changes the used value of the 'contain' property so as to turn on layout containment, style containment, and
+    // paint containment for the element.
+    if (computed_values().content_visibility() == CSS::ContentVisibility::Auto)
+        return true;
+
+    return false;
+}
+// https://drafts.csswg.org/css-contain-2/#containment-paint
+bool Node::has_paint_containment() const
+{
+    // However, giving an element paint containment has no effect if any of the following are true:
+
+    // - if the element does not generate a principal box (as is the case with 'display: contents' or 'display: none')
+    // Note: This is the principal box
+
+    // - if its principal box is an internal table box other than 'table-cell'
+    if (display().is_internal_table() && !display().is_table_cell())
+        return false;
+
+    // - if its principal box is an internal ruby box or a non-atomic inline-level box
+    // FIXME: Implement this
+
+    if (computed_values().contain().paint_containment)
+        return true;
+
+    // https://drafts.csswg.org/css-contain-2/#valdef-content-visibility-auto
+    // Changes the used value of the 'contain' property so as to turn on layout containment, style containment, and
+    // paint containment for the element.
+    if (computed_values().content_visibility() == CSS::ContentVisibility::Auto)
+        return true;
+
+    return false;
+}
+
 bool NodeWithStyleAndBoxModelMetrics::should_create_inline_continuation() const
 {
     // This node must have an inline parent.