Reviewed by Ken, Richard.

    Reviewed by Ken, Richard.

        <rdar://problem/3996383> REGRESSION (Mail): Deleting all of first line also deletes line ending

        Problem was the placeholder check was based on 0 height block, but the block in this
        case is the BODY, which has other content even though the paragraph is gone.

        * khtml/editing/htmlediting.cpp:
        (khtml::CompositeEditCommand::insertBlockPlaceholder):
        Now does insert instead of append!

        (khtml::CompositeEditCommand::appendBlockPlaceholder):
        New.  Actually does append.

        (khtml::CompositeEditCommand::addBlockPlaceholderIfNeeded):
        Renamed from insertBlockPlaceholderIfNeeded because it can insert or append.  Also accepts "force insert" flag.

        (khtml::CompositeEditCommand::removeBlockPlaceholder):
        Renamed for succinctness from removeBlockPlaceholderIfNeeded.

        (khtml::DeleteSelectionCommand::insertPlaceholderForAncestorBlockContent):
        (khtml::DeleteSelectionCommand::moveNodesAfterNode):
        Use renamed methods.

        (khtml::DeleteSelectionCommand::doApply):
        Use addBlockPlaceholderIfNeeded "force insert" flag if deleting whole paragraphs did not leave an empty one.

        (khtml::InsertParagraphSeparatorCommand::doApply):
        (khtml::InsertParagraphSeparatorInQuotedContentCommand::doApply):
        (khtml::InsertTextCommand::input):
        Use renamed methods.

        * khtml/editing/htmlediting.h:
        Renamed and new methods per above.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@8787 268f45cc-cd09-0410-ab3c-d52691b4dbfc