Oilpan: Introduce TempRangeScope to avoid needless Range attaches on Document.

Source/core/html/HTMLTextFormControlElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 299 matching lines @@
     newSelection.setIsDirectional(direction != SelectionHasNoDirection);
 
     if (LocalFrame* frame = document().frame())
         frame->selection().setSelection(newSelection);
 }
 
 VisiblePosition HTMLTextFormControlElement::visiblePositionForIndex(int index) const
 {
     if (index <= 0)
         return VisiblePosition(firstPositionInNode(innerEditorElement()), DOWNSTREAM);
+    TemporaryRangeScope scope;
     RefPtrWillBeRawPtr<Range> range = Range::create(document());
     range->selectNodeContents(innerEditorElement(), ASSERT_NO_EXCEPTION);
     CharacterIterator it(range.get());
     it.advance(index - 1);
     return VisiblePosition(it.range()->endPosition(), UPSTREAM);
 }
 
 int HTMLTextFormControlElement::indexForVisiblePosition(const VisiblePosition& pos) const
 {
     Position indexPosition = pos.deepEquivalent().parentAnchoredEquivalent();
     if (enclosingTextFormControl(indexPosition) != this)
         return 0;
+    TemporaryRangeScope scope;
     ASSERT(indexPosition.document());
     RefPtrWillBeRawPtr<Range> range = Range::create(*indexPosition.document());
     range->setStart(innerEditorElement(), 0, ASSERT_NO_EXCEPTION);
     range->setEnd(indexPosition.containerNode(), indexPosition.offsetInContainerNode(), ASSERT_NO_EXCEPTION);
     return TextIterator::rangeLength(range.get());
 }
 
 int HTMLTextFormControlElement::selectionStart() const
 {
     if (!isTextFormControl())
@@ skipping 311 matching lines @@
 
     return "ltr";
 }
 
 HTMLElement* HTMLTextFormControlElement::innerEditorElement() const
 {
     return toHTMLElement(userAgentShadowRoot()->getElementById(ShadowElementNames::innerEditor()));
 }
 
 } // namespace Webcore