Reviewed by Adam Barth.

        https://bugs.webkit.org/show_bug.cgi?id=21840
        https://bugs.webkit.org/show_bug.cgi?id=23993

        Fix an editing bug where replacing a selection would result in the
        new text ending up inside nodes that were not visibly included in the
        selection.  Instead, move our destination position out of nodes that
        were not visibly included.

        Two new tests to verify the new behavior.  Because we're now inserting
        outside of some formatting nodes, some span tags are no longer necessary
        for undoing formatting caused by these formatting nodes.

        * editing/deleting/backspace-avoid-preceding-style-expected.txt: Added.
        * editing/deleting/backspace-avoid-preceding-style.html: Added.
        * editing/inserting/replace-at-visible-boundary-expected.txt: Added.
        * editing/inserting/replace-at-visible-boundary.html: Added.
        * platform/mac/editing/deleting/delete-3857753-fix-expected.txt:
        * platform/mac/editing/inserting/insert-div-026-expected.txt:
        * platform/mac/editing/pasteboard/paste-text-at-tabspan-001-expected.txt:
        * platform/mac/editing/pasteboard/paste-text-at-tabspan-002-expected.txt:
        * platform/mac/editing/style/font-family-with-space-expected.txt:
        * platform/mac/editing/style/smoosh-styles-001-expected.txt:
        * platform/mac/editing/style/style-boundary-005-expected.txt:
2010-03-09  Tony Chang  <tony@chromium.org>

        Reviewed by Adam Barth.

        https://bugs.webkit.org/show_bug.cgi?id=21840
        https://bugs.webkit.org/show_bug.cgi?id=23993

        Fix an editing bug where replacing a selection would result in the
        new text ending up inside nodes that were not visibly included in the
        selection.  Instead, move our destination position out of nodes that
        were not visibly included.

        Tests: editing/deleting/backspace-avoid-preceding-style.html
               editing/inserting/replace-at-visible-boundary.html

        * editing/ReplaceSelectionCommand.cpp:
        (WebCore::positionAvoidingPrecedingNodes):
        (WebCore::ReplaceSelectionCommand::doApply):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@55762 268f45cc-cd09-0410-ab3c-d52691b4dbfc