Fix duplicated strings in ADMX templates.

Also fixed the generated <string> IDs, which can't contain "."
characters.

BUG=chromium:429117

Review URL: https://codereview.chromium.org/702793003

git-svn-id: http://grit-i18n.googlecode.com/svn/trunk@181 7262f16d-afe8-6277-6482-052fa10e57b1
6 files changed