Make PositionIterator to skip contents of INPUT/SELECT/TEXTAREA

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

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 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
@@ skipping 2856 matching lines @@
   if (!pos.node())
     return true;
 
   if (isAtomicNode(pos.node()))
     return true;
 
   return pos.atStartOfNode();
 }
 
 template <typename Strategy>
+static PositionTemplate<Strategy> adjustPositionForBackwardIteration(
+    const PositionTemplate<Strategy>& position) {
+  DCHECK(!position.isNull());
+  if (!position.isAfterAnchor())
+    return position;
+  if (isUserSelectContain(*position.anchorNode()))
+    return position.toOffsetInAnchor();
+  return PositionTemplate<Strategy>::editingPositionOf(
+      position.anchorNode(), Strategy::caretMaxOffset(*position.anchorNode()));
+}
+
+template <typename Strategy>
 static PositionTemplate<Strategy> mostBackwardCaretPosition(
     const PositionTemplate<Strategy>& position,
     EditingBoundaryCrossingRule rule) {
   DCHECK(!needsLayoutTreeUpdate(position)) << position;
   TRACE_EVENT0("input", "VisibleUnits::mostBackwardCaretPosition");
 
   Node* startNode = position.anchorNode();
   if (!startNode)
     return PositionTemplate<Strategy>();
 
   // iterate backward from there, looking for a qualified position
   Node* boundary = enclosingVisualBoundary<Strategy>(startNode);
   // FIXME: PositionIterator should respect Before and After positions.
   PositionIteratorAlgorithm<Strategy> lastVisible(
-      position.isAfterAnchor()
-          ? PositionTemplate<Strategy>::editingPositionOf(
-                position.anchorNode(),
-                Strategy::caretMaxOffset(*position.anchorNode()))
-          : position);
+      adjustPositionForBackwardIteration<Strategy>(position));
   PositionIteratorAlgorithm<Strategy> currentPos = lastVisible;
   bool startEditable = hasEditableStyle(*startNode);
   Node* lastNode = startNode;
   bool boundaryCrossed = false;
   for (; !currentPos.atStart(); currentPos.decrement()) {
     Node* currentNode = currentPos.node();
     // Don't check for an editability change if we haven't moved to a different
     // node, to avoid the expense of computing hasEditableStyle().
     if (currentNode != lastNode) {
       // Don't change editability.
@@ skipping 1059 matching lines @@
 
 VisiblePositionInFlatTree previousPositionOf(
     const VisiblePositionInFlatTree& visiblePosition,
     EditingBoundaryCrossingRule rule) {
   DCHECK(visiblePosition.isValid()) << visiblePosition;
   return previousPositionOfAlgorithm<EditingInFlatTreeStrategy>(
       visiblePosition.deepEquivalent(), rule);
 }
 
 }  // namespace blink