[LayoutNG] Removes per-child state from NGBlockLayoutAlgorithm.

Removes curr_bfc_offset_, curr_child_margins_, curr_margin_strut_ in
favour of stack variables.

This clears up the information flow between children, and makes it clear
*which* margin strut, etc is being used for a particular child's
positioning. (E.g. the OOFPositioned child's positioning was difficult
to determine before).

This introduces one regression which I'll investigate separately (static
position is weird with abs-pos legacy children now) - so I've removed the
LayoutNG CQ bot.

BUG=635619

Review-Url: https://codereview.chromium.org/2899413002
Cr-Commit-Position: refs/heads/master@{#476354}

third_party/WebKit/LayoutTests/TestExpectations

@@ -502,7 +502,6 @@ crbug.com/719646 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/block-in-in
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/block-in-inline-percents-001.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/block-non-replaced-height-005.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/block-non-replaced-width-007.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/block-replaced-width-002.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/block-replaced-width-006.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/blocks-013.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/blocks-017.xht [ Failure ]
@@ -553,13 +552,7 @@ crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-bloc
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-block-non-replaced-height-002.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-block-replaced-height-008.xht [ Skip ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-block-valign-002.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-non-replaced-height-002.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-non-replaced-height-003.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-replaced-height-008.xht [ Skip ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-replaced-width-001.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-replaced-width-002.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-replaced-width-003.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-replaced-width-006.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-replaced-width-012.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-replaced-width-013.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-replaced-width-015.xht [ Failure ]
@@ -596,6 +589,7 @@ crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/max-height-
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/max-height-081.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/max-height-082.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/max-height-090.xht [ Failure ]
+crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/inline-replaced-width-006.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/max-height-092.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/max-height-093.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/max-height-101.xht [ Failure ]
@@ -737,8 +731,6 @@ crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/positioning
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/positioning-float-002.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/relpos-calcs-004.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/relpos-calcs-005.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/top-007.xht [ Crash ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/top-008.xht [ Crash ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/top-019.xht [ Crash Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/top-020.xht [ Crash Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/top-031.xht [ Crash Failure ]
@@ -758,7 +750,7 @@ crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/top-104.xht
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/top-113.xht [ Crash Failure ]
 
 ### virtual/layout_ng/fast/block/basic
-crbug.com/635619 virtual/layout_ng/fast/block/basic/003.html [ Failure ]
+crbug.com/635619 virtual/layout_ng/fast/block/basic/001.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/basic/006.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/basic/011.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/basic/013.html [ Failure ]
@@ -825,7 +817,6 @@ crbug.com/635619 virtual/layout_ng/fast/block/float/br-with-clear.html [ Failure
 crbug.com/635619 virtual/layout_ng/fast/block/float/canvas-with-floats-marked-for-layout.html [ Crash ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/centered-float-avoidance-complexity.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/checkbox-and-radio-avoid-floats.html [ Failure ]
-crbug.com/635619 virtual/layout_ng/fast/block/float/clamped-right-float.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/clear-element-too-wide-for-containing-block.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/clear-intruding-floats-when-moving-to-inline-parent-3.html [ Crash Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/clear-to-fit.html [ Failure ]

third_party/WebKit/Source/core/layout/ng/inline/ng_inline_layout_algorithm.cc

@@ -55,11 +55,11 @@ NGInlineLayoutAlgorithm::NGInlineLayoutAlgorithm(
   // Only resolve our BFC offset if we know that we are non-empty as we may
   // need to pass through our margin strut.
   if (!inline_node->Items().IsEmpty()) {
-    NGLogicalOffset bfc_offset = ConstraintSpace().BfcOffset();
-    bfc_offset.block_offset += ConstraintSpace().MarginStrut().Sum();
-    MaybeUpdateFragmentBfcOffset(ConstraintSpace(), bfc_offset,
+    LayoutUnit bfc_block_offset = ConstraintSpace().BfcOffset().block_offset;
+    bfc_block_offset += ConstraintSpace().MarginStrut().Sum();
+    MaybeUpdateFragmentBfcOffset(ConstraintSpace(), bfc_block_offset,
                                  &container_builder_);
-    PositionPendingFloats(bfc_offset.block_offset, &container_builder_,
+    PositionPendingFloats(bfc_block_offset, &container_builder_,
                           MutableConstraintSpace());
   }
 

third_party/WebKit/Source/core/layout/ng/ng_block_layout_algorithm.h

@@ -18,10 +18,12 @@ namespace blink {
 
 class NGConstraintSpace;
 class NGLayoutResult;
+struct NGInflowChildData;
+struct NGPreviousInflowPosition;
 
 // Updates the fragment's BFC offset if it's not already set.
 void MaybeUpdateFragmentBfcOffset(const NGConstraintSpace&,
-                                  const NGLogicalOffset&,
+                                  LayoutUnit bfc_block_offset,
                                   NGFragmentBuilder* builder);
 
 // Positions pending floats starting from {@origin_block_offset} and relative
@@ -52,15 +54,19 @@ class CORE_EXPORT NGBlockLayoutAlgorithm
 
   // Creates a new constraint space for the current child.
   RefPtr<NGConstraintSpace> CreateConstraintSpaceForChild(
-      const NGLogicalOffset& child_bfc_offset,
-      const NGLayoutInputNode&);
+      const NGLayoutInputNode& child,
+      const NGInflowChildData& child_data);
 
   // @return Estimated BFC offset for the "to be layout" child.
-  NGLogicalOffset PrepareChildLayout(NGLayoutInputNode*);
+  NGInflowChildData PrepareChildLayout(const NGPreviousInflowPosition&,
+                                       NGLayoutInputNode*);
 
-  void FinishChildLayout(const NGConstraintSpace&,
-                         const NGLayoutInputNode* child,
-                         NGLayoutResult*);
+  NGPreviousInflowPosition FinishChildLayout(
+      const NGConstraintSpace&,
+      const NGPreviousInflowPosition& prev_data,
+      const NGInflowChildData& child_data,
+      const NGLayoutInputNode* child,
+      NGLayoutResult*);
 
   // Positions the fragment that establishes a new formatting context.
   //
@@ -81,7 +87,10 @@ class CORE_EXPORT NGBlockLayoutAlgorithm
   //    then it will be placed there and we collapse its margin.
   // 2) If #new-fc is too big then we need to clear its position and place it
   //    below #float ignoring its vertical margin.
-  NGLogicalOffset PositionNewFc(const NGBoxFragment&,
+  NGLogicalOffset PositionNewFc(const NGLayoutInputNode& child,
+                                const NGPreviousInflowPosition&,
+                                const NGBoxFragment&,
+                                const NGInflowChildData& child_data,
                                 const NGConstraintSpace& child_space);
 
   // Positions the fragment that knows its BFC offset.
@@ -95,12 +104,16 @@ class CORE_EXPORT NGBlockLayoutAlgorithm
   //   <div style="padding: 1px">
   //     <div id="empty-div" style="margins: 1px"></div>
   NGLogicalOffset PositionWithParentBfc(const NGConstraintSpace&,
+                                        const NGInflowChildData& child_data,
                                         const NGBoxFragment&);
 
-  NGLogicalOffset PositionLegacy(const NGConstraintSpace& child_space);
+  NGLogicalOffset PositionLegacy(const NGConstraintSpace& child_space,
+                                 const NGInflowChildData& child_data);
 
-  void HandleOutOfFlowPositioned(NGBlockNode*);
-  void HandleFloating(NGBlockNode*, NGBlockBreakToken*);
+  void HandleOutOfFlowPositioned(const NGPreviousInflowPosition&, NGBlockNode*);
+  void HandleFloating(const NGPreviousInflowPosition&,
+                      NGBlockNode*,
+                      NGBlockBreakToken*);
 
   // Final adjustments before fragment creation. We need to prevent the
   // fragment from crossing fragmentainer boundaries, and rather create a break
@@ -112,6 +125,7 @@ class CORE_EXPORT NGBlockLayoutAlgorithm
   // or {@code known_fragment_offset} if the fragment knows it's offset
   // @return Fragment's offset relative to the fragment's parent.
   NGLogicalOffset CalculateLogicalOffset(
+      const NGBoxStrut& child_margins,
       const WTF::Optional<NGLogicalOffset>& known_fragment_offset);
 
   NGLogicalSize child_available_size_;
@@ -120,10 +134,6 @@ class CORE_EXPORT NGBlockLayoutAlgorithm
   NGBoxStrut border_and_padding_;
   LayoutUnit content_size_;
   LayoutUnit max_inline_size_;
-  // MarginStrut for the previous child.
-  NGMarginStrut curr_margin_strut_;
-  NGLogicalOffset curr_bfc_offset_;
-  NGBoxStrut curr_child_margins_;
 };
 
 }  // namespace blink