Let Selection.collapse remember a raw Position instead of a canonicalized one.

Source/core/editing/FrameSelection.cpp

 /*
  * Copyright (C) 2004, 2008, 2009, 2010 Apple 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 1385 matching lines @@
 
     if (selectStartTarget && !selectStartTarget->dispatchEvent(Event::createCancelableBubble(EventTypeNames::selectstart)))
         return;
 
     VisibleSelection newSelection(VisibleSelection::selectionFromContentsOfNode(root.get()));
     setSelection(newSelection);
     selectFrameElementInParentIfFullySelected();
     notifyRendererOfSelectionChange(UserTriggered);
 }
 
-bool FrameSelection::setSelectedRange(Range* range, EAffinity affinity, SetSelectionOptions options)
+bool FrameSelection::setSelectedRange(Range* range, EAffinity affinity, bool isDirectional, SetSelectionOptions options)
 {
     if (!range || !range->startContainer() || !range->endContainer())
         return false;
     ASSERT(range->startContainer()->document() == range->endContainer()->document());
 
     // Non-collapsed ranges are not allowed to start at the end of a line that is wrapped,
     // they start at the beginning of the next line instead
     m_logicalRange = nullptr;
     stopObservingVisibleSelectionChangeIfNecessary();
 
-    VisibleSelection newSelection(range, affinity);
+    VisibleSelection newSelection(range, affinity, isDirectional);
     setSelection(newSelection, options);
 
     m_logicalRange = range->cloneRange();
     startObservingVisibleSelectionChange();
 
     return true;
 }
 
 PassRefPtrWillBeRawPtr<Range> FrameSelection::firstRange() const
 {
@@ skipping 454 matching lines @@
     sel.showTreeForThis();
 }
 
 void showTree(const WebCore::FrameSelection* sel)
 {
     if (sel)
         sel->showTreeForThis();
 }
 
 #endif