Make |NGFragmentItems::DirtyLinesFromNeedsLayout| static

This patch changes |NGFragmentItems::DirtyLinesFromNeedsLayout|
to static, matching other |DirtyLines*| in crrev.com/c/2505262.

Also removes two calls to |FragmentItems|, which we need to
eliminate to support block fragmentation, in DCHECK and test.

This patch has no behavior changes.

Bug: 1061423
Change-Id: I13c8ad366935f0d7e2c37230030da8d649259b61
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2505707Reviewed-by: Kent Tamura <tkent@chromium.org>
Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Morten Stenshorne <mstensho@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#822592}

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

@@ -62,7 +62,7 @@ class NGFragmentItemTest : public NGLayoutTest,
     LayoutBlockFlow* block_flow = GetLayoutBlockFlowByElementId(id);
     const NGPhysicalBoxFragment* fragment = block_flow->GetPhysicalFragment(0);
     const NGFragmentItems* items = fragment->Items();
-    items->DirtyLinesFromNeedsLayout(block_flow);
+    NGFragmentItems::DirtyLinesFromNeedsLayout(*block_flow);
     const NGFragmentItem* end_reusable_item =
         items->EndOfReusableItems(*fragment);
 

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

@@ -333,19 +333,25 @@ void NGFragmentItems::DirtyFirstItem(const LayoutBlockFlow& container) {
   }
 }
 
+// static
 void NGFragmentItems::DirtyLinesFromNeedsLayout(
-    const LayoutBlockFlow* container) const {
-  DCHECK_EQ(this, container->FragmentItems());
+    const LayoutBlockFlow& container) {
+  DCHECK(std::any_of(container.PhysicalFragments().begin(),
+                     container.PhysicalFragments().end(),
+                     [](const NGPhysicalBoxFragment& fragment) {
+                       return fragment.HasItems();
+                     }));
+
   // Mark dirty for the first top-level child that has |NeedsLayout|.
   //
   // TODO(kojii): We could mark first descendant to increase reuse
   // opportunities. Doing this complicates the logic, especially when culled
   // inline is involved, and common case is to append to large IFC. Choose
   // simpler logic and faster to check over more reuse opportunities.
-  for (LayoutObject* child = container->FirstChild(); child;
+  for (LayoutObject* child = container.FirstChild(); child;
        child = child->NextSibling()) {
     if (child->NeedsLayout()) {
-      DirtyLinesFromChangedChild(*child, *container);
+      DirtyLinesFromChangedChild(*child, container);
       return;
     }
   }

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

@@ -82,7 +82,7 @@ class CORE_EXPORT NGFragmentItems {
                                          const LayoutBlockFlow& container);
 
   // Mark items dirty from |LayoutObject::NeedsLayout| flags.
-  void DirtyLinesFromNeedsLayout(const LayoutBlockFlow* block_flow) const;
+  static void DirtyLinesFromNeedsLayout(const LayoutBlockFlow& block_flow);
 
   // The byte size of this instance.
   constexpr static wtf_size_t ByteSizeFor(wtf_size_t count) {

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

@@ -141,16 +141,23 @@ class NGInlineNodeTest : public NGLayoutTest {
     return end_offsets;
   }
 
-  void TestAnyItemsAreDirty(LayoutBlockFlow* block_flow, bool expected) {
-    const NGFragmentItems* items = block_flow->FragmentItems();
-    items->DirtyLinesFromNeedsLayout(block_flow);
-    // Check |NGFragmentItem::IsDirty| directly without using
-    // |EndOfReusableItems|. This is different from the line cache logic, but
-    // some items may not be reusable even if |!IsDirty()|.
-    const bool is_any_items_dirty =
-        std::any_of(items->Items().begin(), items->Items().end(),
-                    [](const NGFragmentItem& item) { return item.IsDirty(); });
-    EXPECT_EQ(is_any_items_dirty, expected);
+  void TestAnyItemsAreDirty(const LayoutBlockFlow& block_flow, bool expected) {
+    NGFragmentItems::DirtyLinesFromNeedsLayout(block_flow);
+    for (const NGPhysicalBoxFragment& fragment :
+         block_flow.PhysicalFragments()) {
+      if (const NGFragmentItems* items = fragment.Items()) {
+        // Check |NGFragmentItem::IsDirty| directly without using
+        // |EndOfReusableItems|. This is different from the line cache logic,
+        // but some items may not be reusable even if |!IsDirty()|.
+        for (const NGFragmentItem& item : items->Items()) {
+          if (item.IsDirty()) {
+            EXPECT_TRUE(expected);
+            return;
+          }
+        }
+      }
+    }
+    EXPECT_FALSE(expected);
   }
 
   scoped_refptr<const ComputedStyle> style_;
@@ -686,7 +693,7 @@ TEST_P(StyleChangeTest, NeedsCollectInlinesOnStyle) {
 
   if (data.is_line_dirty &&
       RuntimeEnabledFeatures::LayoutNGFragmentItemEnabled()) {
-    TestAnyItemsAreDirty(To<LayoutBlockFlow>(container->GetLayoutObject()),
+    TestAnyItemsAreDirty(*To<LayoutBlockFlow>(container->GetLayoutObject()),
                          *data.is_line_dirty);
   }
 

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

@@ -992,7 +992,9 @@ bool NGBlockLayoutAlgorithm::TryReuseFragmentsFromCache(
   DCHECK(previous_items);
 
   // Find reusable lines. Fail if no items are reusable.
-  previous_items->DirtyLinesFromNeedsLayout(inline_node.GetLayoutBlockFlow());
+  // TODO(kojii): |DirtyLinesFromNeedsLayout| is needed only once for a
+  // |LayoutBlockFlow|, not for every fragment.
+  NGFragmentItems::DirtyLinesFromNeedsLayout(*inline_node.GetLayoutBlockFlow());
   const NGFragmentItem* end_item =
       previous_items->EndOfReusableItems(previous_fragment);
   DCHECK(end_item);