<rdar://problem/4359736> Support outlining ability with lists

        Added Mail SPI for list level changes.  It is SPI because it is not complete support
        for outlining.  See <rdar://problem/4457070> "API for html lists as note outlines".
        Additional support is to end a list when return is typed on empty list item.

        * WebCore.vcproj/WebCore/WebCore.vcproj:
        * WebCore.xcodeproj/project.pbxproj:
        Added ModifySelectionListLevelCommand.cpp and ModifySelectionListLevelCommand.h
        
        * bridge/mac/WebCoreFrameBridge.h:
        * bridge/mac/WebCoreFrameBridge.mm:
        (-[WebCoreFrameBridge canIncreaseSelectionListLevel]):
        (-[WebCoreFrameBridge canDecreaseSelectionListLevel]):
        (-[WebCoreFrameBridge increaseSelectionListLevel]):
        (-[WebCoreFrameBridge decreaseSelectionListLevel]):
        Supply list level calls in the bridge.
        
        * editing/InsertParagraphSeparatorCommand.cpp:
        (WebCore::createListItemElement):
        New.  Creates an li.
        
        (WebCore::InsertParagraphSeparatorCommand::doApply):
        - slight logic cleanup
        - on empty list item, end the list
        
        * editing/ModifySelectionListLevelCommand.cpp: Added.
        (WebCore::ModifySelectionListLevelCommand::ModifySelectionListLevelCommand):
        (WebCore::ModifySelectionListLevelCommand::preservesTypingStyle):
        (WebCore::ModifySelectionListLevelCommand::doApply):
        (WebCore::ModifySelectionListLevelCommand::canIncreaseSelectionListLevel):
        (WebCore::ModifySelectionListLevelCommand::canDecreaseSelectionListLevel):
        (WebCore::ModifySelectionListLevelCommand::increaseSelectionListLevel):
        (WebCore::ModifySelectionListLevelCommand::decreaseSelectionListLevel):
        (WebCore::modifySelectionListLevel):
        (WebCore::getStartEndListChildren):
        (WebCore::canIncreaseListLevel):
        (WebCore::canDecreaseListLevel):
        (WebCore::ModifySelectionListLevelCommand::insertSiblingNodeRangeBefore):
        (WebCore::ModifySelectionListLevelCommand::insertSiblingNodeRangeAfter):
        (WebCore::ModifySelectionListLevelCommand::appendSiblingNodeRange):
        (WebCore::ModifySelectionListLevelCommand::increaseListLevel):
        (WebCore::ModifySelectionListLevelCommand::decreaseListLevel):
        * editing/ModifySelectionListLevelCommand.h: Added.
        New editing command for adjusting the list level.
        
        * editing/ReplaceSelectionCommand.cpp:
        (WebCore::ReplaceSelectionCommand::doApply):
        Slight logic cleanup

        * editing/htmlediting.cpp:
        (WebCore::isListElement):
        (WebCore::enclosingListChild):
        New helpers.
        
        (WebCore::isTableElement):
        Allow caller to pass 0... return false in that case.
        
        * editing/htmlediting.h:
        New helpers.
        
        * rendering/RenderContainer.cpp:
        (WebCore::updateListMarkerNumbers):
        Allow for list children that are not li nodes.  Ignore and continue rather than stopping.
        
        (WebCore::RenderContainer::addChild):
        Allow for nil beforeChild, meaning "add at end".



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@13075 268f45cc-cd09-0410-ab3c-d52691b4dbfc