Draw the theme overlay.  I hadn't implemented this previously because I didn't have an example theme that does this.
Draw the theme overlay.  I hadn't implemented this previously because
I didn't have an example theme that does this.

TEST=Install the Folders theme from the theme gallery and you should
  see a paperclip and some paper in the theme.

Review URL: http://codereview.chromium.org/165002


git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@22539 0039d316-1c4b-4281-b951-d872f2087c98

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