Part of Bug 16532: Inspector should highlight nodes in page when
        hovering over nodes in Inspector's interface

        <http://bugs.webkit.org/show_bug.cgi?id=16532>
        <rdar://problem/5712896>

        The inspected node is no longer highlighted (unless, of course, you
        hover over it).

        Reviewed by Tim Hatcher.

        * page/inspector/DocumentPanel.js:
        (WebInspector.DocumentPanel):
          - Don't highlight the focused node when the DOM tree is shown
          - Added mousemove/mouseout event listeners to set/clear the
            highlighted node. These are added to the root of the DOM tree
            instead of to each individual list item to avoid flashing as the
            mouse moves between nodes.
        (WebInspector.DocumentPanel.set focusedDOMNode): Don't highlight the
        focused node.
        (WebInspector.DocumentPanel._onmousemove): Highlight the node under
        the mouse.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@31190 268f45cc-cd09-0410-ab3c-d52691b4dbfc