Fix missing favicon for chrome://extensions/
Fix missing favicon for chrome://extensions/

It was mistakenly removed in r40468.

BUG=None
TEST=None
TBR=aa@chromium.org

Review URL: http://codereview.chromium.org/669261

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@40881 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser