Changes grit_info.py to respect target_platform when generating output lists.
Changes grit_info.py to respect target_platform when generating output lists.

Patch from issue 22923027, by rohitrao@chromium.org

Review URL: https://codereview.chromium.org/23102022
imuse2012/grit-i18n,camny125/grit-i18n,camny125/grit-i18n,imuse2012/grit-i18n