Introduce composed tree version of VisiblePosition

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 42 matching lines @@
 VisiblePositionTemplate<Strategy>::VisiblePositionTemplate()
 {
 }
 
 template <typename Strategy>
 VisiblePositionTemplate<Strategy>::VisiblePositionTemplate(const PositionWithAffinityTemplate<Strategy>& positionWithAffinity)
     : m_positionWithAffinity(positionWithAffinity)
 {
 }
 
-template <typename Strategy>
-VisiblePositionTemplate<Strategy> VisiblePositionTemplate<Strategy>::createWithoutCanonicalization(const PositionWithAffinityTemplate<Strategy>& canonicalized)
+template<typename Strategy>
+VisiblePositionTemplate<Strategy> VisiblePositionTemplate<Strategy>::create(const PositionWithAffinityTemplate<Strategy>& positionWithAffinity)
 {
-    return VisiblePositionTemplate<Strategy>(canonicalized);
-}
-
-template<typename Strategy>
-static PositionWithAffinityTemplate<Strategy> createVisiblePositionAlgorithm(const PositionAlgorithm<Strategy>& position, TextAffinity affinity)
-{
-    const PositionAlgorithm<Strategy> deepPosition = canonicalPositionOf(position);
+    const PositionAlgorithm<Strategy> deepPosition = canonicalPositionOf(positionWithAffinity.position());
     if (deepPosition.isNull())
-        return PositionWithAffinityTemplate<Strategy>();
-    if (affinity == TextAffinity::Downstream)
-        return PositionWithAffinityTemplate<Strategy>(deepPosition);
+        return VisiblePositionTemplate<Strategy>();
+    const PositionWithAffinityTemplate<Strategy> downstreamPosition(deepPosition);
+    if (positionWithAffinity.affinity() == TextAffinity::Downstream)
+        return VisiblePositionTemplate<Strategy>(downstreamPosition);
 
     // When not at a line wrap, make sure to end up with
     // |TextAffinity::Downstream| affinity.
-    if (inSameLine(PositionWithAffinityTemplate<Strategy>(deepPosition), PositionWithAffinityTemplate<Strategy>(deepPosition, TextAffinity::Upstream)))
-        return PositionWithAffinityTemplate<Strategy>(deepPosition);
-    return PositionWithAffinityTemplate<Strategy>(deepPosition, TextAffinity::Upstream);
+    const PositionWithAffinityTemplate<Strategy> upstreamPosition(deepPosition, TextAffinity::Upstream);
+    if (inSameLine(downstreamPosition, upstreamPosition))
+        return VisiblePositionTemplate<Strategy>(downstreamPosition);
+    return VisiblePositionTemplate<Strategy>(upstreamPosition);
 }
 
 VisiblePosition createVisiblePosition(const Position& position, TextAffinity affinity)
 {
-    return VisiblePosition::createWithoutCanonicalization(createVisiblePositionAlgorithm<EditingStrategy>(position, affinity));
+    return createVisiblePosition(PositionWithAffinity(position, affinity));
 }
 
 VisiblePosition createVisiblePosition(const PositionWithAffinity& positionWithAffinity)
 {
-    return createVisiblePosition(positionWithAffinity.position(), positionWithAffinity.affinity());
+    return VisiblePosition::create(positionWithAffinity);
 }
 
-VisiblePosition createVisiblePosition(const PositionInComposedTree& position, TextAffinity affinity)
+VisiblePositionInComposedTree createVisiblePosition(const PositionInComposedTree& position, TextAffinity affinity)
 {
-    PositionInComposedTreeWithAffinity canonicalized = createVisiblePositionAlgorithm<EditingInComposedTreeStrategy>(position, affinity);
-    return VisiblePosition::createWithoutCanonicalization(PositionWithAffinity(toPositionInDOMTree(canonicalized.position()), canonicalized.affinity()));
+    return VisiblePositionInComposedTree::create(PositionInComposedTreeWithAffinity(position, affinity));
+}
+
+VisiblePosition createVisiblePositionInDOMTree(const Position& position, TextAffinity affinity)
+{
+    return createVisiblePosition(position, affinity);
+}
+
+VisiblePosition createVisiblePositionInDOMTree(const PositionInComposedTree& position, TextAffinity affinity)
+{
+    const VisiblePositionInComposedTree visiblePosition = createVisiblePosition(position);
+    return createVisiblePosition(toPositionInDOMTree(visiblePosition.deepEquivalent()), affinity);
 }
 
 #ifndef NDEBUG
 
 template<typename Strategy>
 void VisiblePositionTemplate<Strategy>::debugPosition(const char* msg) const
 {
     if (isNull()) {
         fprintf(stderr, "Position [%s]: null\n", msg);
         return;
     }
     deepEquivalent().debugPosition(msg);
 }
 
 template<typename Strategy>
 void VisiblePositionTemplate<Strategy>::formatForDebugger(char* buffer, unsigned length) const
 {
     deepEquivalent().formatForDebugger(buffer, length);
 }
 
 template<typename Strategy>
 void VisiblePositionTemplate<Strategy>::showTreeForThis() const
 {
     deepEquivalent().showTreeForThis();
 }
 
 #endif
 
 template class CORE_TEMPLATE_EXPORT VisiblePositionTemplate<EditingStrategy>;
+template class CORE_TEMPLATE_EXPORT VisiblePositionTemplate<EditingInComposedTreeStrategy>;
 
 } // namespace blink
 
 #ifndef NDEBUG
 
 void showTree(const blink::VisiblePosition* vpos)
 {
     if (vpos)
         vpos->showTreeForThis();
     else
         fprintf(stderr, "Cannot showTree for (nil) VisiblePosition.\n");
 }
 
 void showTree(const blink::VisiblePosition& vpos)
 {
     vpos.showTreeForThis();
 }
 
 #endif