1 files changed, 51 insertions, 3 deletions

diff --git a/components/layout_2020/layout_box_base.rs b/components/layout_2020/layout_box_base.rs
index 0de9987bde7..bb2d37698f1 100644
--- a/components/layout_2020/layout_box_base.rs
+++ b/components/layout_2020/layout_box_base.rs
@@ -2,15 +2,20 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+use std::fmt::{Debug, Formatter};
+
+use app_units::Au;
 use atomic_refcell::AtomicRefCell;
 use servo_arc::Arc;
 use style::properties::ComputedValues;
 
-use crate::ConstraintSpace;
 use crate::context::LayoutContext;
-use crate::fragment_tree::BaseFragmentInfo;
+use crate::formatting_contexts::Baselines;
+use crate::fragment_tree::{BaseFragmentInfo, CollapsedBlockMargins, Fragment, SpecificLayoutInfo};
 use crate::geom::SizeConstraint;
+use crate::positioned::PositioningContext;
 use crate::sizing::{ComputeInlineContentSizes, InlineContentSizesResult};
+use crate::{ConstraintSpace, ContainingBlockSize};
 
 /// A box tree node that handles containing information about style and the original DOM
 /// node or pseudo-element that it is based on. This also handles caching of layout values
@@ -18,12 +23,12 @@ use crate::sizing::{ComputeInlineContentSizes, InlineContentSizesResult};
 /// passes.
 ///
 /// In the future, this will hold layout results to support incremental layout.
-#[derive(Debug)]
 pub(crate) struct LayoutBoxBase {
     pub base_fragment_info: BaseFragmentInfo,
     pub style: Arc<ComputedValues>,
     pub cached_inline_content_size:
         AtomicRefCell<Option<(SizeConstraint, InlineContentSizesResult)>>,
+    pub cached_layout_result: AtomicRefCell<Option<CacheableLayoutResultAndInputs>>,
 }
 
 impl LayoutBoxBase {
@@ -32,6 +37,7 @@ impl LayoutBoxBase {
             base_fragment_info,
             style,
             cached_inline_content_size: AtomicRefCell::default(),
+            cached_layout_result: AtomicRefCell::default(),
         }
     }
 
@@ -58,3 +64,45 @@ impl LayoutBoxBase {
         result
     }
 }
+
+impl Debug for LayoutBoxBase {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), std::fmt::Error> {
+        f.debug_struct("LayoutBoxBase").finish()
+    }
+}
+
+#[derive(Clone)]
+pub(crate) struct CacheableLayoutResult {
+    pub fragments: Vec<Fragment>,
+
+    /// <https://drafts.csswg.org/css2/visudet.html#root-height>
+    pub content_block_size: Au,
+
+    /// If this layout is for a block container, this tracks the collapsable size
+    /// of start and end margins and whether or not the block container collapsed through.
+    pub collapsible_margins_in_children: CollapsedBlockMargins,
+
+    /// The contents of a table may force it to become wider than what we would expect
+    /// from 'width' and 'min-width'. This is the resulting inline content size,
+    /// or None for non-table layouts.
+    pub content_inline_size_for_table: Option<Au>,
+
+    /// The offset of the last inflow baseline of this layout in the content area, if
+    /// there was one. This is used to propagate baselines to the ancestors of `display:
+    /// inline-block`.
+    pub baselines: Baselines,
+
+    /// Whether or not this layout depends on the containing block size.
+    pub depends_on_block_constraints: bool,
+
+    /// Additional information of this layout that could be used by Javascripts and devtools.
+    pub specific_layout_info: Option<SpecificLayoutInfo>,
+}
+
+pub(crate) struct CacheableLayoutResultAndInputs {
+    pub result: CacheableLayoutResult,
+
+    pub containing_block_for_children_size: ContainingBlockSize,
+
+    pub positioning_context: PositioningContext,
+}