Fix bug where we fail to install an extension that has an empty permissions array in its manifest.
Fix bug where we fail to install an extension that has an empty
permissions array in its manifest.

This was caused an old attempt to display a warning in this
situation, back when we were ambitious.

BUG=22157
TEST=Install extension associated with bug.

Review URL: http://codereview.chromium.org/213009

git-svn-id: http://src.chromium.org/svn/trunk/src@26534 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 5d5ae1fcc564c2652b3c7f996b52d6f431f6e1b6
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser