Fix proxy settings for Gnome >=2.26
Fix proxy settings for Gnome >=2.26

Proxy settings are set using Gnome's network properties dialog, by running the
binary directly.  The binary was renamed from gnome-system-preferences to
gnome-system-properties in Janurary 2009, so to ensure the dialog works on both
newer and older systems, this patch searches the users PATH for the binary to use.

Upstream rename: http://git.gnome.org/cgit/gnome-control-center/commit/?id=4f1b6aafba338a267b6c1b911ceb33358b2eca09

BUG=17756
TEST='Under the Hood' -> 'Change proxy settings' still works on Ubuntu Hardy as well as Ubuntu Jaunty.

Review URL: http://codereview.chromium.org/160146
Patch from Joel Stanley.

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@21870 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