[layoutng] Return PhysicalFragment as a raw pointer

This avoids refcounting overhead where it's not needed.

R=eae@chromium.org, mstensho@chromium.org

Change-Id: Ic9303d8325ee9369b1df3f5a16a5c357da9d87bf
Reviewed-on: https://chromium-review.googlesource.com/c/1306395Reviewed-by: Morten Stenshorne <mstensho@chromium.org>
Reviewed-by: Emil A Eklund <eae@chromium.org>
Commit-Queue: Christian Biesinger <cbiesinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#603722}

third_party/blink/renderer/core/layout/ng/inline/ng_inline_layout_algorithm_test.cc

@@ -52,22 +52,19 @@ TEST_F(NGInlineLayoutAlgorithmTest, BreakToken) {
   NGInlineChildLayoutContext context;
   scoped_refptr<NGLayoutResult> layout_result =
       inline_node.Layout(constraint_space, nullptr, &context);
-  auto* line1 =
-      ToNGPhysicalLineBoxFragment(layout_result->PhysicalFragment().get());
+  auto* line1 = ToNGPhysicalLineBoxFragment(layout_result->PhysicalFragment());
   EXPECT_FALSE(line1->BreakToken()->IsFinished());
 
   // Perform 2nd layout with the break token from the 1st line.
   scoped_refptr<NGLayoutResult> layout_result2 =
       inline_node.Layout(constraint_space, line1->BreakToken(), &context);
-  auto* line2 =
-      ToNGPhysicalLineBoxFragment(layout_result2->PhysicalFragment().get());
+  auto* line2 = ToNGPhysicalLineBoxFragment(layout_result2->PhysicalFragment());
   EXPECT_FALSE(line2->BreakToken()->IsFinished());
 
   // Perform 3rd layout with the break token from the 2nd line.
   scoped_refptr<NGLayoutResult> layout_result3 =
       inline_node.Layout(constraint_space, line2->BreakToken(), &context);
-  auto* line3 =
-      ToNGPhysicalLineBoxFragment(layout_result3->PhysicalFragment().get());
+  auto* line3 = ToNGPhysicalLineBoxFragment(layout_result3->PhysicalFragment());
   EXPECT_TRUE(line3->BreakToken()->IsFinished());
 }
 
@@ -188,8 +185,7 @@ TEST_F(NGInlineLayoutAlgorithmTest, ContainerBorderPadding) {
       NGConstraintSpace::CreateFromLayoutObject(*block_flow);
   scoped_refptr<NGLayoutResult> layout_result = block_node.Layout(space);
 
-  auto* block_box =
-      ToNGPhysicalBoxFragment(layout_result->PhysicalFragment().get());
+  auto* block_box = ToNGPhysicalBoxFragment(layout_result->PhysicalFragment());
   EXPECT_TRUE(layout_result->BfcBlockOffset().has_value());
   EXPECT_EQ(0, layout_result->BfcBlockOffset().value());
   EXPECT_EQ(0, layout_result->BfcLineOffset());
@@ -223,8 +219,7 @@ TEST_F(NGInlineLayoutAlgorithmTest, MAYBE_VerticalAlignBottomReplaced) {
   scoped_refptr<NGLayoutResult> layout_result =
       inline_node.Layout(space, nullptr, &context);
 
-  auto* line =
-      ToNGPhysicalLineBoxFragment(layout_result->PhysicalFragment().get());
+  auto* line = ToNGPhysicalLineBoxFragment(layout_result->PhysicalFragment());
   EXPECT_EQ(LayoutUnit(96), line->Size().height);
   NGPhysicalOffset img_offset = line->Children()[0].Offset();
   EXPECT_EQ(LayoutUnit(0), img_offset.top);

third_party/blink/renderer/core/layout/ng/inline/ng_inline_node_test.cc

@@ -115,7 +115,7 @@ class NGInlineNodeTest : public NGLayoutTest {
             .Layout();
 
     const NGPhysicalLineBoxFragment* line =
-        ToNGPhysicalLineBoxFragment(result->PhysicalFragment().get());
+        ToNGPhysicalLineBoxFragment(result->PhysicalFragment());
     for (const auto& child : line->Children()) {
       fragments_out->push_back(ToNGPhysicalTextFragment(child.get()));
     }

third_party/blink/renderer/core/layout/ng/inline/ng_line_box_fragment_builder.h

@@ -121,8 +121,7 @@ class CORE_EXPORT NGLineBoxFragmentBuilder final
     bool HasBidiLevel() const { return bidi_level != 0xff; }
     bool IsPlaceholder() const { return !HasFragment() && !HasBidiLevel(); }
     const NGPhysicalFragment* PhysicalFragment() const {
-      return layout_result ? layout_result->PhysicalFragment().get()
-                           : fragment.get();
+      return layout_result ? layout_result->PhysicalFragment() : fragment.get();
     }
   };
 

third_party/blink/renderer/core/layout/ng/layout_ng_block_flow.cc

@@ -70,7 +70,7 @@ void LayoutNGBlockFlow::UpdateBlockLayout(bool relayout_children) {
     descendant.node.UseOldOutOfFlowPositioning();
 
   const NGPhysicalBoxFragment* fragment =
-      ToNGPhysicalBoxFragment(result->PhysicalFragment().get());
+      ToNGPhysicalBoxFragment(result->PhysicalFragment());
 
   // This object has already been positioned in legacy layout by our containing
   // block. Copy the position and place the fragment.
@@ -241,8 +241,8 @@ void LayoutNGBlockFlow::UpdateOutOfFlowBlockLayout() {
        result->OutOfFlowPositionedDescendants())
     descendant.node.UseOldOutOfFlowPositioning();
 
-  scoped_refptr<const NGPhysicalBoxFragment> fragment =
-      ToNGPhysicalBoxFragment(result->PhysicalFragment().get());
+  const NGPhysicalBoxFragment* fragment =
+      ToNGPhysicalBoxFragment(result->PhysicalFragment());
   DCHECK_GT(fragment->Children().size(), 0u);
   // Copy sizes of all child fragments to Legacy.
   // There could be multiple fragments, when this node has descendants whose

third_party/blink/renderer/core/layout/ng/layout_ng_flexible_box.cc

@@ -33,7 +33,7 @@ void LayoutNGFlexibleBox::UpdateBlockLayout(bool relayout_children) {
     descendant.node.UseOldOutOfFlowPositioning();
 
   const NGPhysicalBoxFragment* fragment =
-      ToNGPhysicalBoxFragment(result->PhysicalFragment().get());
+      ToNGPhysicalBoxFragment(result->PhysicalFragment());
 
   // Pasted from layout_ng_block_flow. TODO(dgrogan): Factor a utility method.
   const LayoutBlock* containing_block = ContainingBlock();

third_party/blink/renderer/core/layout/ng/layout_ng_mixin.cc

@@ -62,7 +62,7 @@ void LayoutNGMixin<Base>::ResetNGInlineNodeData() {
 template <typename Base>
 const NGPhysicalBoxFragment* LayoutNGMixin<Base>::CurrentFragment() const {
   if (cached_result_)
-    return ToNGPhysicalBoxFragment(cached_result_->PhysicalFragment().get());
+    return ToNGPhysicalBoxFragment(cached_result_->PhysicalFragment());
   return nullptr;
 }
 

third_party/blink/renderer/core/layout/ng/layout_ng_table_cell.cc

@@ -33,7 +33,7 @@ void LayoutNGTableCell::UpdateBlockLayout(bool relayout_children) {
     descendant.node.UseOldOutOfFlowPositioning();
 
   const NGPhysicalBoxFragment* fragment =
-      ToNGPhysicalBoxFragment(result->PhysicalFragment().get());
+      ToNGPhysicalBoxFragment(result->PhysicalFragment());
 
   const LayoutBox* section = LocationContainer();
   NGPhysicalOffset physical_offset;

third_party/blink/renderer/core/layout/ng/ng_base_layout_algorithm_test.cc

@@ -37,9 +37,8 @@ NGBaseLayoutAlgorithmTest::RunBlockLayoutAlgorithmForElement(Element* element) {
 
   scoped_refptr<NGLayoutResult> result =
       NGBlockLayoutAlgorithm(node, space).Layout();
-  return std::make_pair(
-      ToNGPhysicalBoxFragment(result->PhysicalFragment().get()),
-      std::move(space));
+  return std::make_pair(ToNGPhysicalBoxFragment(result->PhysicalFragment()),
+                        std::move(space));
 }
 
 scoped_refptr<const NGPhysicalBoxFragment>

third_party/blink/renderer/core/layout/ng/ng_block_layout_algorithm_test.cc

@@ -39,7 +39,7 @@ class NGBlockLayoutAlgorithmTest : public NGBaseLayoutAlgorithmTest {
     scoped_refptr<NGLayoutResult> result =
         NGBlockLayoutAlgorithm(node, space).Layout();
 
-    return ToNGPhysicalBoxFragment(result->PhysicalFragment().get());
+    return ToNGPhysicalBoxFragment(result->PhysicalFragment());
   }
 
   MinMaxSize RunComputeMinAndMax(NGBlockNode node) {

third_party/blink/renderer/core/layout/ng/ng_column_layout_algorithm.cc

@@ -116,8 +116,8 @@ scoped_refptr<NGLayoutResult> NGColumnLayoutAlgorithm::Layout() {
                                              break_token.get());
       child_algorithm.SetBoxType(NGPhysicalFragment::kColumnBox);
       scoped_refptr<NGLayoutResult> result = child_algorithm.Layout();
-      scoped_refptr<const NGPhysicalBoxFragment> column(
-          ToNGPhysicalBoxFragment(result->PhysicalFragment().get()));
+      const NGPhysicalBoxFragment* column =
+          ToNGPhysicalBoxFragment(result->PhysicalFragment());
 
       NGLogicalOffset logical_offset(column_inline_offset, column_block_offset);
       container_builder_.AddChild(*result, logical_offset);

third_party/blink/renderer/core/layout/ng/ng_column_layout_algorithm_test.cc

@@ -33,7 +33,7 @@ class NGColumnLayoutAlgorithmTest : public NGBaseLayoutAlgorithmTest {
     scoped_refptr<NGLayoutResult> result =
         NGBlockLayoutAlgorithm(node, space).Layout();
 
-    return ToNGPhysicalBoxFragment(result->PhysicalFragment().get());
+    return ToNGPhysicalBoxFragment(result->PhysicalFragment());
   }
 
   scoped_refptr<const NGPhysicalBoxFragment> RunBlockLayoutAlgorithm(

third_party/blink/renderer/core/layout/ng/ng_fieldset_layout_algorithm_test.cc

@@ -35,7 +35,7 @@ class NGFieldsetLayoutAlgorithmTest : public NGBaseLayoutAlgorithmTest {
     scoped_refptr<NGLayoutResult> result =
         NGBlockLayoutAlgorithm(node, space).Layout();
 
-    return ToNGPhysicalBoxFragment(result->PhysicalFragment().get());
+    return ToNGPhysicalBoxFragment(result->PhysicalFragment());
   }
 
   scoped_refptr<const NGPhysicalBoxFragment> RunBlockLayoutAlgorithm(

third_party/blink/renderer/core/layout/ng/ng_floats_utils.cc

@@ -214,7 +214,7 @@ LayoutUnit ComputeMarginBoxInlineSizeForUnpositionedFloat(
       unpositioned_float);
   DCHECK(unpositioned_float->layout_result);
 
-  const auto& fragment = unpositioned_float->layout_result->PhysicalFragment();
+  const auto* fragment = unpositioned_float->layout_result->PhysicalFragment();
   DCHECK(fragment);
   DCHECK(!fragment->BreakToken() || fragment->BreakToken()->IsFinished());
 

third_party/blink/renderer/core/layout/ng/ng_layout_result.h

@@ -43,7 +43,7 @@ class CORE_EXPORT NGLayoutResult : public RefCounted<NGLayoutResult> {
   NGLayoutResult(const NGLayoutResult&);
   ~NGLayoutResult();
 
-  scoped_refptr<const NGPhysicalFragment> PhysicalFragment() const {
+  const NGPhysicalFragment* PhysicalFragment() const {
     return root_fragment_.get();
   }
   NGPhysicalOffset Offset() const { return root_fragment_.Offset(); }

third_party/blink/renderer/core/layout/ng/ng_out_of_flow_layout_part.cc

@@ -362,7 +362,7 @@ scoped_refptr<NGLayoutResult> NGOutOfFlowLayoutPart::LayoutDescendant(
     layout_result = GenerateFragment(descendant.node, container_info,
                                      block_estimate, node_position);
 
-    DCHECK(layout_result->PhysicalFragment().get());
+    DCHECK(layout_result->PhysicalFragment());
     NGFragment fragment(descendant_writing_mode,
                         *layout_result->PhysicalFragment());
 

third_party/blink/renderer/core/layout/ng/ng_page_layout_algorithm.cc

@@ -52,8 +52,8 @@ scoped_refptr<NGLayoutResult> NGPageLayoutAlgorithm::Layout() {
     NGBlockLayoutAlgorithm child_algorithm(Node(), child_space,
                                            break_token.get());
     scoped_refptr<NGLayoutResult> result = child_algorithm.Layout();
-    scoped_refptr<const NGPhysicalBoxFragment> page(
-        ToNGPhysicalBoxFragment(result->PhysicalFragment().get()));
+    const NGPhysicalBoxFragment* page =
+        ToNGPhysicalBoxFragment(result->PhysicalFragment());
 
     container_builder_.AddChild(*result, page_offset);