Reviewed by Darin.

    Reviewed by Darin.

        <rdar://problem/5415006> Command Left in a To Do causes caret to disappear

        * editing/selection/mixed-editability-8.html: Added.
        * editing/selection/mixed-editability-9.html: Added.
        * platform/mac/editing/selection: Added.
        * platform/mac/editing/selection/mixed-editability-8-expected.checksum: Added.
        * platform/mac/editing/selection/mixed-editability-8-expected.png: Added.
        * platform/mac/editing/selection/mixed-editability-8-expected.txt: Added.
        * platform/mac/editing/selection/mixed-editability-9-expected.checksum: Added.
        * platform/mac/editing/selection/mixed-editability-9-expected.png: Added.
        * platform/mac/editing/selection/mixed-editability-9-expected.txt: Added.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@25281 268f45cc-cd09-0410-ab3c-d52691b4dbfc