Geolocation: extract struct Geoposition out of geolocation.mojom

This CL extracts the struct Geoposition out of geolocation.mojom 
into a file on its own. No new code.


Bug: 
Change-Id: I6350537ccd19d1da0b02f3c8489fa39a06740376
Reviewed-on: https://chromium-review.googlesource.com/543577
Reviewed-by: Colin Blundell <[email protected]>
Reviewed-by: Tom Sepez <[email protected]>
Commit-Queue: Miguel Casas <[email protected]>
Cr-Commit-Position: refs/heads/master@{#481777}
4 files changed