Invalidate caret during paint invalidation

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
@@ skipping 472 matching lines @@
   void computeBlockPreferredLogicalWidths(LayoutUnit& minLogicalWidth,
                                           LayoutUnit& maxLogicalWidth) const;
 
   bool isSelectionRoot() const;
 
  public:
   bool hasCursorCaret() const;
   bool hasDragCaret() const;
   bool hasCaret() const { return hasCursorCaret() || hasDragCaret(); }
 
+  class MutableForPainting : public LayoutBox::MutableForPainting {
+   public:
+    void setHasPreviousCaretVisualRects(bool b) {
+      static_cast<LayoutBlock&>(m_layoutObject).m_hasPreviousCaretVisualRects =
+          b;
+    }
+
+   protected:
+    friend class LayoutBlock;
+    MutableForPainting(const LayoutBlock& layoutBlock)
+        : LayoutBox::MutableForPainting(layoutBlock) {}
+  };
+
+  MutableForPainting getMutableForPainting() const {
+    return MutableForPainting(*this);
+  }
+
+  // Called when a cursor caret or drag caret in this LayoutBlock need paint

[chrishtr, 2017/01/31 22:51:04]

Nit: "needs"

+  // invalidation, e.g. when its color or visibility changes. When a caret
+  // just changes location, use setMayNeedPaintInvalidation() instead.
+  void setCaretsNeedPaintInvalidation() {
+    if (m_caretsNeedPaintInvalidation)
+      return;
+    m_caretsNeedPaintInvalidation = true;
+    setMayNeedPaintInvalidation();
+  }
+  bool caretsNeedPaintInvalidation() const {
+    return m_caretsNeedPaintInvalidation;
+  }
+
+  bool hasPreviousCaretVisualRects() const {
+    return m_hasPreviousCaretVisualRects;
+  }
+
  protected:
   PaintInvalidationReason invalidatePaintIfNeeded(
       const PaintInvalidationState&) override;
   PaintInvalidationReason invalidatePaintIfNeeded(
       const PaintInvalidatorContext&) const override;
 
+  void clearPaintInvalidationFlags() override {
+    LayoutBox::clearPaintInvalidationFlags();
+    m_caretsNeedPaintInvalidation = false;
+  }
+
+  void clearPreviousVisualRects() override;
+
+#if DCHECK_IS_ON()
+  bool paintInvalidationStateIsDirty() const override {
+    return LayoutBox::paintInvalidationStateIsDirty() ||
+           m_caretsNeedPaintInvalidation;
+  }
+#endif
+
  private:
   LayoutRect localCaretRect(InlineBox*,
                             int caretOffset,
                             LayoutUnit* extraWidthToEndOfLine = nullptr) final;
   bool isInlineBoxWrapperActuallyChild() const;
 
   Position positionForBox(InlineBox*, bool start = true) const;
 
   // End helper functions and structs used by layoutBlockChildren.
 
@@ skipping 36 matching lines @@
   unsigned m_hasPercentHeightDescendants : 1;
 
   // When an object ceases to establish a fragmentation context (e.g. the
   // LayoutView when we're no longer printing), we need a deep layout
   // afterwards, to clear all pagination struts. Likewise, when an object
   // becomes fragmented, we need to re-lay out the entire subtree. There might
   // be forced breaks somewhere in there that we suddenly have to pay attention
   // to, for all we know.
   unsigned m_paginationStateChanged : 1;
 
+  // Indicates if we have saved previous cursor and/or drag caret visual rects
+  // for the LayoutBlock in BlockPaintInvalidator.
+  unsigned m_hasPreviousCaretVisualRects : 1;
+
+  unsigned m_caretsNeedPaintInvalidation : 1;
+
   // FIXME: This is temporary as we move code that accesses block flow
   // member variables out of LayoutBlock and into LayoutBlockFlow.
   friend class LayoutBlockFlow;
 
   // This is necessary for now for interoperability between the old and new
   // layout code. Primarily for calling layoutPositionedObjects at the moment.
   friend class NGBlockNode;
 
  public:
   // TODO(lunalu): Temporary in order to ensure compatibility with existing
   // layout test results.
   virtual void adjustChildDebugRect(LayoutRect&) const {}
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutBlock, isLayoutBlock());
 
 }  // namespace blink
 
 #endif  // LayoutBlock_h