Get rid of a redundant argument DOWNSTREAM from VisiblePosition constructor call sites

Source/core/editing/VisiblePosition.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Portions Copyright (c) 2011 Motorola Mobility, 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
@@ skipping 69 matching lines @@
 }
 
 VisiblePosition VisiblePosition::previous(EditingBoundaryCrossingRule rule) const
 {
     Position pos = previousVisuallyDistinctCandidate(m_deepPosition);
 
     // return null visible position if there is no previous visible position
     if (pos.atStartOfTree())
         return VisiblePosition();
 
-    VisiblePosition prev = VisiblePosition(pos, DOWNSTREAM);
+    VisiblePosition prev = VisiblePosition(pos);
     ASSERT(prev.deepEquivalent() != m_deepPosition);
 
 #if ENABLE(ASSERT)
     // we should always be able to make the affinity DOWNSTREAM, because going previous from an
     // UPSTREAM position can never yield another UPSTREAM position (unless line wrap length is 0!).
     if (prev.isNotNull() && m_affinity == UPSTREAM) {
         ASSERT(inSameLine(PositionWithAffinity(prev.deepEquivalent(), DOWNSTREAM), PositionWithAffinity(prev.deepEquivalent(), UPSTREAM)));
     }
 #endif
 
@@ skipping 156 matching lines @@
     }
 }
 
 VisiblePosition VisiblePosition::left() const
 {
     Position pos = leftVisuallyDistinctCandidate();
     // FIXME: Why can't we move left from the last position in a tree?
     if (pos.atStartOfTree() || pos.atEndOfTree())
         return VisiblePosition();
 
-    VisiblePosition left = VisiblePosition(pos, DOWNSTREAM);
+    VisiblePosition left = VisiblePosition(pos);
     ASSERT(left.deepEquivalent() != m_deepPosition);
 
     return directionOfEnclosingBlock(left.deepEquivalent()) == LTR ? honorEditingBoundaryAtOrBefore(left) : honorEditingBoundaryAtOrAfter(left);
 }
 
 Position VisiblePosition::rightVisuallyDistinctCandidate() const
 {
     Position p = m_deepPosition;
     if (p.isNull())
         return Position();
@@ skipping 141 matching lines @@
     }
 }
 
 VisiblePosition VisiblePosition::right() const
 {
     Position pos = rightVisuallyDistinctCandidate();
     // FIXME: Why can't we move left from the last position in a tree?
     if (pos.atStartOfTree() || pos.atEndOfTree())
         return VisiblePosition();
 
-    VisiblePosition right = VisiblePosition(pos, DOWNSTREAM);
+    VisiblePosition right = VisiblePosition(pos);
     ASSERT(right.deepEquivalent() != m_deepPosition);
 
     return directionOfEnclosingBlock(right.deepEquivalent()) == LTR ? honorEditingBoundaryAtOrAfter(right) : honorEditingBoundaryAtOrBefore(right);
 }
 
 template <typename Strategy>
 PositionWithAffinityTemplate<Strategy> honorEditingBoundaryAtOrBeforeAlgorithm(const PositionWithAffinityTemplate<Strategy>& pos, const PositionAlgorithm<Strategy>& anchor)
 {
     if (pos.isNull())
         return pos;
@@ skipping 325 matching lines @@
     else
         fprintf(stderr, "Cannot showTree for (nil) VisiblePosition.\n");
 }
 
 void showTree(const blink::VisiblePosition& vpos)
 {
     vpos.showTreeForThis();
 }
 
 #endif