Get rid of redundant member function PositionAlgorithm<Strategy>::{upstream,downstream}

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 102 matching lines @@
     ASSERT_NOT_REACHED();
     return honorEditingBoundaryAtOrBefore(prev);
 }
 
 Position VisiblePosition::leftVisuallyDistinctCandidate() const
 {
     Position p = m_deepPosition;
     if (p.isNull())
         return Position();
 
-    Position downstreamStart = p.downstream();
+    Position downstreamStart = mostForwardCaretPosition(p);
     TextDirection primaryDirection = primaryDirectionOf(*p.anchorNode());
 
     while (true) {
         InlineBoxPosition boxPosition = computeInlineBoxPosition(p, m_affinity, primaryDirection);
         InlineBox* box = boxPosition.inlineBox;
         int offset = boxPosition.offsetInBox;
         if (!box)
             return primaryDirection == LTR ? previousVisuallyDistinctCandidate(m_deepPosition) : nextVisuallyDistinctCandidate(m_deepPosition);
 
         LayoutObject* layoutObject = &box->layoutObject();
@@ skipping 112 matching lines @@
                     level = box->bidiLevel();
                 }
                 layoutObject = &box->layoutObject();
                 offset = primaryDirection == LTR ? box->caretMinOffset() : box->caretMaxOffset();
             }
             break;
         }
 
         p = Position::editingPositionOf(layoutObject->node(), offset);
 
-        if ((isVisuallyEquivalentCandidate(p) && p.downstream() != downstreamStart) || p.atStartOfTree() || p.atEndOfTree())
+        if ((isVisuallyEquivalentCandidate(p) && mostForwardCaretPosition(p) != downstreamStart) || p.atStartOfTree() || p.atEndOfTree())
             return p;
 
         ASSERT(p != m_deepPosition);
     }
 }
 
 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);
     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();
 
-    Position downstreamStart = p.downstream();
+    Position downstreamStart = mostForwardCaretPosition(p);
     TextDirection primaryDirection = primaryDirectionOf(*p.anchorNode());
 
     while (true) {
         InlineBoxPosition boxPosition = computeInlineBoxPosition(p, m_affinity, primaryDirection);
         InlineBox* box = boxPosition.inlineBox;
         int offset = boxPosition.offsetInBox;
         if (!box)
             return primaryDirection == LTR ? nextVisuallyDistinctCandidate(m_deepPosition) : previousVisuallyDistinctCandidate(m_deepPosition);
 
         LayoutObject* layoutObject = &box->layoutObject();
@@ skipping 115 matching lines @@
                     level = box->bidiLevel();
                 }
                 layoutObject = &box->layoutObject();
                 offset = primaryDirection == LTR ? box->caretMaxOffset() : box->caretMinOffset();
             }
             break;
         }
 
         p = Position::editingPositionOf(layoutObject->node(), offset);
 
-        if ((isVisuallyEquivalentCandidate(p) && p.downstream() != downstreamStart) || p.atStartOfTree() || p.atEndOfTree())
+        if ((isVisuallyEquivalentCandidate(p) && mostForwardCaretPosition(p) != downstreamStart) || p.atStartOfTree() || p.atEndOfTree())
             return p;
 
         ASSERT(p != m_deepPosition);
     }
 }
 
 VisiblePosition VisiblePosition::right() const
 {
     Position pos = rightVisuallyDistinctCandidate();
     // FIXME: Why can't we move left from the last position in a tree?
@@ skipping 113 matching lines @@
     // That must mean that |pos| is not editable. Return the next position after pos that is in the same editable region as this position
     return firstEditableVisiblePositionAfterPositionInRoot(pos.deepEquivalent(), highestRoot);
 }
 
 template <typename PositionType>
 static PositionType canonicalizeCandidate(const PositionType& candidate)
 {
     if (candidate.isNull())
         return PositionType();
     ASSERT(isVisuallyEquivalentCandidate(candidate));
-    PositionType upstream = candidate.upstream();
+    PositionType upstream = mostBackwardCaretPosition(candidate);
     if (isVisuallyEquivalentCandidate(upstream))
         return upstream;
     return candidate;
 }
 
 template <typename PositionType>
 static PositionType canonicalPosition(const PositionType& passedPosition)
 {
     // Sometimes updating selection positions can be extremely expensive and occur
     // frequently.  Often calling preventDefault on mousedown events can avoid
@@ skipping 11 matching lines @@
     // the appropriate layoutObject for VisiblePosition's like these, or b) canonicalize to the rightmost candidate
     // unless the affinity is upstream.
     if (position.isNull())
         return PositionType();
 
     ASSERT(position.document());
     position.document()->updateLayoutIgnorePendingStylesheets();
 
     Node* node = position.computeContainerNode();
 
-    PositionType candidate = position.upstream();
+    PositionType candidate = mostBackwardCaretPosition(position);
     if (isVisuallyEquivalentCandidate(candidate))
         return candidate;
-    candidate = position.downstream();
+    candidate = mostForwardCaretPosition(position);
     if (isVisuallyEquivalentCandidate(candidate))
         return candidate;
 
     // When neither upstream or downstream gets us to a candidate (upstream/downstream won't leave
     // blocks or enter new ones), we search forward and backward until we find one.
     PositionType next = canonicalizeCandidate(nextCandidate(position));
     PositionType prev = canonicalizeCandidate(previousCandidate(position));
     Node* nextNode = next.anchorNode();
     Node* prevNode = prev.anchorNode();
 
@@ skipping 61 matching lines @@
     if (!inSameLine(PositionWithAffinityTemplate<Strategy>(deepPosition), PositionWithAffinityTemplate<Strategy>(deepPosition, TextAffinity::Upstream)))
         return;
     m_affinity = TextAffinity::Downstream;
 }
 
 UChar32 VisiblePosition::characterAfter() const
 {
     // We canonicalize to the first of two equivalent candidates, but the second
     // of the two candidates is the one that will be inside the text node
     // containing the character after this visible position.
-    Position pos = m_deepPosition.downstream();
+    Position pos = mostForwardCaretPosition(m_deepPosition);
     if (!pos.isOffsetInAnchor())
         return 0;
     Node* containerNode = pos.computeContainerNode();
     if (!containerNode || !containerNode->isTextNode())
         return 0;
     unsigned offset = static_cast<unsigned>(pos.offsetInContainerNode());
     Text* textNode = toText(containerNode);
     unsigned length = textNode->length();
     if (offset >= length)
         return 0;
@@ skipping 89 matching lines @@
     else
         fprintf(stderr, "Cannot showTree for (nil) VisiblePosition.\n");
 }
 
 void showTree(const blink::VisiblePosition& vpos)
 {
     vpos.showTreeForThis();
 }
 
 #endif