CANCELLED Merge SelectionAdjuster into VisibleSelection part 1

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

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SelectionAdjuster_h
 #define SelectionAdjuster_h
 
 #include "core/editing/VisibleSelection.h"
-#include "wtf/Allocator.h"
 
 namespace blink {
 
-// |SelectionAdjuster| adjusts positions in |VisibleSelection| directly without
-// calling |validate()|. Users of |SelectionAdjuster| should keep invariant of
-// |VisibleSelection|, e.g. all positions are canonicalized.
-class CORE_EXPORT SelectionAdjuster final {
-  STATIC_ONLY(SelectionAdjuster);
+// TODO(xiaochengh): Move everything to VisibleSelection.cpp.
 
- public:
-  static void adjustSelectionToAvoidCrossingShadowBoundaries(VisibleSelection*);
-  static void adjustSelectionToAvoidCrossingShadowBoundaries(
-      VisibleSelectionInFlatTree*);
-};
+enum class AdjustDirection { kAdjustNone, kAdjustStart, kAdjustEnd };
+
+std::pair<AdjustDirection, Position> adjustmentToAvoidCrossingShadowBoundaries(
+    const VisibleSelection&);
+std::pair<AdjustDirection, PositionInFlatTree>
+adjustmentToAvoidCrossingShadowBoundaries(const VisibleSelectionInFlatTree&);
 
 }  // namespace blink
 
 #endif  // SelectionAdjuster_h