Revert Tizen changes to support changing the system location provider.

This reverts the following commits:
* 9132a4f "[Tizen] Enable geolocation for Tizen"
* 801bdbf "[Tizen] Use Tizen system location provider for geolocation
           subsystem"

They have not been needed since at least M35(!), when Chromium commit
5038bce99 ("location: Refactor LocationProvider") made it possible to
change the system location provider in ContentBrowserClient.

We can now do everything on the Crosswalk side, and also fixes an issue
with building Crosswalk for Tizen with -Dcomponent=shared_library, as
libcontent.so would not have an implementation of
content::NewSystemLocationProvider() (this did not happen before the
content layer was being built as a static library linked into the
Crosswalk binary that had an implementation for that symbol).
Merge pull request #214 from rakuco/revert-tizen-geolocation-changes

Revert Tizen changes to support changing the system location provider.