LibWeb: Use correct box edge when looking for space between floats

Userland/Libraries/LibWeb/Layout/BlockFormattingContext.cpp

@@ -626,7 +626,7 @@ void BlockFormattingContext::layout_floating_box(Box const& box, BlockContainer
                 offset_from_edge = box_state.content_width() + box_state.margin_box_right();
         };
 
-        auto box_in_root_rect = border_box_rect_in_ancestor_coordinate_space(box, root(), m_state);
+        auto box_in_root_rect = content_box_rect_in_ancestor_coordinate_space(box, root(), m_state);
         float y_in_root = box_in_root_rect.y();
         float y = box_state.offset.y();
 

Userland/Libraries/LibWeb/Layout/InlineFormattingContext.cpp

@@ -52,7 +52,7 @@ BlockFormattingContext const& InlineFormattingContext::parent() const
 float InlineFormattingContext::leftmost_x_offset_at(float y) const
 {
     // NOTE: Floats are relative to the BFC root box, not necessarily the containing block of this IFC.
-    auto box_in_root_rect = border_box_rect_in_ancestor_coordinate_space(containing_block(), parent().root(), m_state);
+    auto box_in_root_rect = content_box_rect_in_ancestor_coordinate_space(containing_block(), parent().root(), m_state);
     float y_in_root = box_in_root_rect.y() + y;
     auto space = parent().space_used_by_floats(y_in_root);
     float containing_block_x = m_containing_block_state.offset.x();
@@ -68,7 +68,7 @@ float InlineFormattingContext::available_space_for_line(float y) const
 
     // NOTE: Floats are relative to the BFC root box, not necessarily the containing block of this IFC.
     auto& root_block = parent().root();
-    auto box_in_root_rect = border_box_rect_in_ancestor_coordinate_space(containing_block(), root_block, m_state);
+    auto box_in_root_rect = content_box_rect_in_ancestor_coordinate_space(containing_block(), root_block, m_state);
     float y_in_root = box_in_root_rect.y() + y;
     auto space = parent().space_used_by_floats(y_in_root);
 

Userland/Libraries/LibWeb/Layout/LayoutState.cpp

@@ -132,6 +132,26 @@ Gfx::FloatRect border_box_rect_in_ancestor_coordinate_space(Box const& box, Box
     return rect;
 }
 
+Gfx::FloatRect content_box_rect(Box const& box, LayoutState const& state)
+{
+    auto const& box_state = state.get(box);
+    return Gfx::FloatRect { box_state.offset, { box_state.content_width(), box_state.content_height() } };
+}
+
+Gfx::FloatRect content_box_rect_in_ancestor_coordinate_space(Box const& box, Box const& ancestor_box, LayoutState const& state)
+{
+    auto rect = content_box_rect(box, state);
+    for (auto const* current = box.parent(); current; current = current->parent()) {
+        if (current == &ancestor_box)
+            break;
+        if (is<Box>(*current)) {
+            auto const& current_state = state.get(static_cast<Box const&>(*current));
+            rect.translate_by(current_state.offset);
+        }
+    }
+    return rect;
+}
+
 Gfx::FloatRect margin_box_rect_in_ancestor_coordinate_space(Box const& box, Box const& ancestor_box, LayoutState const& state)
 {
     auto rect = margin_box_rect(box, state);

Userland/Libraries/LibWeb/Layout/LayoutState.h

@@ -151,5 +151,7 @@ Gfx::FloatRect margin_box_rect(Box const&, LayoutState const&);
 Gfx::FloatRect margin_box_rect_in_ancestor_coordinate_space(Box const& box, Box const& ancestor_box, LayoutState const&);
 Gfx::FloatRect border_box_rect(Box const&, LayoutState const&);
 Gfx::FloatRect border_box_rect_in_ancestor_coordinate_space(Box const& box, Box const& ancestor_box, LayoutState const&);
+Gfx::FloatRect content_box_rect(Box const&, LayoutState const&);
+Gfx::FloatRect content_box_rect_in_ancestor_coordinate_space(Box const& box, Box const& ancestor_box, LayoutState const&);
 
 }