WebCore:

      Reviewed by Sam.

        - fix http://bugs.webkit.org/show_bug.cgi?id=11997
          Ranges are not fixed after mutation (affects Acid3 test 13)

        Test: fast/dom/Range/mutation.html

        * WebCore.xcodeproj/project.pbxproj: Added NodeWithIndex.h, NodeWithIndexAfter.h,
        and NodeWithIndexBefore.h.

        * dom/CharacterData.cpp:
        (WebCore::CharacterData::setData): Replaced call to Document::removeMarkers
        with call to Document::textRemoved.
        (WebCore::CharacterData::insertData): Replaced call to Document::shiftMarkers
        with call to Document::textInserted.
        (WebCore::CharacterData::deleteData): Replaced call to Document::removeMarkers
        and Document::shiftMarkers with call to Document::textRemoved.
        (WebCore::CharacterData::replaceData): Replaced call to Document::removeMarkers
        and Document::shiftMarkers with call to Document::textRemoved and
        Document::textInserted.
        (WebCore::CharacterData::containsOnlyWhitespace): Tweaked a bit.

        * dom/ContainerNode.cpp:
        (WebCore::ContainerNode::childrenChanged): Added a call to
        Document::nodeChildrenChanged when the nmber of children was changed (and not
        by the parser).
        (WebCore::dispatchChildRemovalEvents): Updated for name change.

        * dom/Document.cpp:
        (WebCore::Document::~Document): Assert that all ranges are gone.
        (WebCore::Document::nodeChildrenChanged): Added. Calls nodeChildrenChanged on
        all ranges.
        (WebCore::Document::nodeWillBeRemoved): Renamed from notifyBeforeNodeRemoval.
        Added code to call nodeWillBeRemoved on all ranges.
        (WebCore::Document::textInserted): Added. Calls textInserted on all ranges and
        also calls shiftMarkers.
        (WebCore::Document::textRemoved): Added. Calls textRemoved on all ranges and also
        calls removeMarkers and shiftMarkers.
        (WebCore::Document::textNodesMerged): Added. Ca