Invalidate first line display item clients when first line style changes

third_party/WebKit/Source/core/layout/LayoutBlock.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 258 matching lines @@
 #if ENABLE(ASSERT)
     void checkPositionedObjectsNeedLayout();
 #endif
 #ifndef NDEBUG
     void showLineTreeAndMark(const InlineBox* = nullptr, const char* = nullptr, const InlineBox* = nullptr, const char* = nullptr, const LayoutObject* = nullptr) const;
 #endif
 
     bool recalcChildOverflowAfterStyleChange();
     bool recalcOverflowAfterStyleChange();
 
+    // An example explaining layout tree structure about first-line style:
+    // <style>
+    //   #enclosingFirstLineStyleBlock::first-line { ... }
+    // </style>
+    // <div id="enclosingFirstLineStyleBlock">
+    //   <div>
+    //     <div id="nearestInnerBlockWithFirstLine">
+    //       [<span>]first line text[</span>]
+    //     </div>
+    //   </div>
+    // </div>
+
+    // Returns the nearest enclosing block (including this block) that contributes a first-line style to our first line.
+    LayoutBlock* enclosingFirstLineStyleBlock() const;
+    // Returns this block or the nearest inner block containing the actual first line.
+    LayoutBlockFlow* nearestInnerBlockWithFirstLine() const;
+
 protected:
     void willBeDestroyed() override;
 
     void dirtyForLayoutFromPercentageHeightDescendants(SubtreeLayoutScope&);
 
     void layout() override;
 
     enum PositionedLayoutBehavior {
         DefaultLayout,
         LayoutOnlyFixedPositionedObjects,
@@ skipping 100 matching lines @@
     bool avoidsFloats() const override { return true; }
 
     bool hitTestContents(HitTestResult&, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction);
     // FIXME-BLOCKFLOW: Remove virtualizaion when all callers have moved to LayoutBlockFlow
     virtual bool hitTestFloats(HitTestResult&, const HitTestLocation&, const LayoutPoint&) { return false; }
 
     virtual bool isPointInOverflowControl(HitTestResult&, const LayoutPoint& locationInContainer, const LayoutPoint& accumulatedOffset) const;
 
     void computeBlockPreferredLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const;
 
-    // Obtains the nearest enclosing block (including this block) that contributes a first-line style to our inline
-    // children.
-    LayoutBlock* firstLineBlock() const override;
-
     LayoutObject* hoverAncestor() const final;
     void updateDragState(bool dragOn) final;
     void childBecameNonInline(LayoutObject* child) final;
 
     bool isSelectionRoot() const;
 
     void absoluteRects(Vector<IntRect>&, const LayoutPoint& accumulatedOffset) const override;
     void absoluteQuads(Vector<FloatQuad>&, bool* wasFixed) const override;
 
 public:
@@ skipping 76 matching lines @@
     // FIXME: This is temporary as we move code that accesses block flow
     // member variables out of LayoutBlock and into LayoutBlockFlow.
     friend class LayoutBlockFlow;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutBlock, isLayoutBlock());
 
 } // namespace blink
 
 #endif // LayoutBlock_h