Get rid of flat tree version of createVisibleSelection() taking two VisiblePositionInFlatTree

third_party/WebKit/Source/core/editing/PendingSelection.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 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 64 matching lines @@
                                           PositionMoveType::CodeUnit)
                          : end;
     selection.setWithoutValidation(start, endPosition);
     return selection;
   }
 
   const VisiblePositionInFlatTree& visibleStart = createVisiblePosition(
       start, selectionType == SelectionType::RangeSelection
                  ? TextAffinity::Downstream
                  : affinity);
+  if (visibleStart.isNull())
+    return VisibleSelectionInFlatTree();
   if (paintBlockCursor) {
-    VisiblePositionInFlatTree visibleExtent =
-        createVisiblePosition(end, affinity);
-    visibleExtent = nextPositionOf(visibleExtent, CanSkipOverEditingBoundary);
-    return createVisibleSelection(visibleStart, visibleExtent);
+    const VisiblePositionInFlatTree visibleExtent = nextPositionOf(
+        createVisiblePosition(end, affinity), CanSkipOverEditingBoundary);
+    if (visibleExtent.isNull())
+      return VisibleSelectionInFlatTree();
+    SelectionInFlatTree::Builder builder;
+    builder.collapse(visibleStart.toPositionWithAffinity());
+    builder.extend(visibleExtent.deepEquivalent());
+    return createVisibleSelection(builder.build());
   }
   const VisiblePositionInFlatTree visibleEnd =
       createVisiblePosition(end, selectionType == SelectionType::RangeSelection
                                      ? TextAffinity::Upstream
                                      : affinity);
-  return createVisibleSelection(visibleStart, visibleEnd);
+  if (visibleEnd.isNull())
+    return VisibleSelectionInFlatTree();
+  SelectionInFlatTree::Builder builder;
+  builder.collapse(visibleStart.toPositionWithAffinity());
+  builder.extend(visibleEnd.deepEquivalent());
+  return createVisibleSelection(builder.build());
 }
 
 void PendingSelection::commit(LayoutView& layoutView) {
   if (!hasPendingSelection())
     return;
   DCHECK(!layoutView.needsLayout());
   m_hasPendingSelection = false;
 
   const VisibleSelectionInFlatTree& originalSelection =
       m_frameSelection->visibleSelection<EditingInFlatTreeStrategy>();
@@ skipping 44 matching lines @@
   DCHECK(layoutView == endLayoutObject->view());
   layoutView.setSelection(startLayoutObject, startPos.computeEditingOffset(),
                           endLayoutObject, endPos.computeEditingOffset());
 }
 
 DEFINE_TRACE(PendingSelection) {
   visitor->trace(m_frameSelection);
 }
 
 }  // namespace blink