Introduce LocalCaretRect for refactoring Local{Caret,Selection}RectPosition()

third_party/WebKit/Source/core/editing/VisibleUnits.h

 /*
  * Copyright (C) 2004 Apple Computer, Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 46 matching lines @@
   bool operator==(const InlineBoxPosition& other) const {
     return inline_box == other.inline_box &&
            offset_in_box == other.offset_in_box;
   }
 
   bool operator!=(const InlineBoxPosition& other) const {
     return !operator==(other);
   }
 };
 
+// This struct represents local caret rectangle in |layout_object|.
+struct LocalCaretRect {
+  LayoutObject* layout_object = nullptr;
+  LayoutRect rect;
+
+  LocalCaretRect() = default;
+  LocalCaretRect(LayoutObject* layout_object, const LayoutRect& rect)
+      : layout_object(layout_object), rect(rect) {}
+
+  bool IsEmpty() const { return !layout_object || rect.IsEmpty(); }
+  FloatQuad LocalToAbsoluteQuad() const;

[Xiaocheng, 2017/06/08 21:00:42]

This function is only used within VisibleUnits.cpp.

If it's not going to be used by follow-up patches, I prefer hiding it as a
static function.

[yosin_UTC9, 2017/06/09 06:13:29]

Done.

+};
+
 // The print for |InlineBoxPosition| is available only for testing
 // in "webkit_unit_tests", and implemented in
 // "core/editing/VisibleUnitsTest.cpp".
 std::ostream& operator<<(std::ostream&, const InlineBoxPosition&);
 
 CORE_EXPORT LayoutObject* AssociatedLayoutObjectOf(const Node&,
                                                    int offset_in_node);
 
 // offset functions on Node
 CORE_EXPORT int CaretMinOffset(const Node*);
@@ skipping 236 matching lines @@
                          TextDirection primary_direction);
 CORE_EXPORT InlineBoxPosition
 ComputeInlineBoxPosition(const PositionInFlatTree&, TextAffinity);
 CORE_EXPORT InlineBoxPosition
 ComputeInlineBoxPosition(const PositionInFlatTree&,
                          TextAffinity,
                          TextDirection primary_direction);
 CORE_EXPORT InlineBoxPosition ComputeInlineBoxPosition(const VisiblePosition&);
 
 // Rect is local to the returned layoutObject
-CORE_EXPORT LayoutRect LocalCaretRectOfPosition(const PositionWithAffinity&,
-                                                LayoutObject*&);
-CORE_EXPORT LayoutRect
-LocalCaretRectOfPosition(const PositionInFlatTreeWithAffinity&, LayoutObject*&);
+CORE_EXPORT LocalCaretRect
+LocalCaretRectOfPosition(const PositionWithAffinity&);
+CORE_EXPORT LocalCaretRect
+LocalCaretRectOfPosition(const PositionInFlatTreeWithAffinity&);
 bool HasRenderedNonAnonymousDescendantsWithHeight(LayoutObject*);
 
 // Returns a hit-tested VisiblePosition for the given point in contents-space
 // coordinates.
 CORE_EXPORT VisiblePosition VisiblePositionForContentsPoint(const IntPoint&,
                                                             LocalFrame*);
 
 CORE_EXPORT bool RendersInDifferentPosition(const Position&, const Position&);
 
 CORE_EXPORT Position SkipWhitespace(const Position&);
@@ skipping 26 matching lines @@
                                             const VisiblePosition&,
                                             EditableType);
 
 Position PreviousRootInlineBoxCandidatePosition(Node*,
                                                 const VisiblePosition&,
                                                 EditableType);
 
 }  // namespace blink
 
 #endif  // VisibleUnits_h