Terriko/cynara geolocation

This patch inserts cynara checks for the geolocation privilege into the browser process on Tizen.  This is necessary to ensure that the geolocation API is available only to webapps that have explicitly asked for this privilege on Tizen, since geolocation is one of the five privileges mediated by the browser rather than the extension process on Tizen.

There will be two other sets of changes related to this one in order to provide complete protection.
1. Modifications to the installer to register permissions needed with cynara https://github.com/crosswalk-project/crosswalk/pull/2518
2. Modifications to ensure that the Extension Process and Render Process are run with appropriate per-app SMACK labels.  https://github.com/crosswalk-project/crosswalk/pull/2397/

This patch obsoletes BUG=XWALK-2092 and is part of the solution to XWALK-553

Notes:
- This needs more extensive testing with a geolocation-capable device, but I don't have one available to me.

[edit: removing things that have been resolved in latest commit]

@pozdnyakov 
Calls to `cynara_creds_socket_get_client` and `cynara_creds_socket_get_user` will allocate memory for the strings. The caller should take care of freeing `client_id` and `user_id`.