Fit Data Bounds doesn't reveal all the data on the map when geocentroid is active

[ytzlax]

Kibana version: 5.4.1

Elasticsearch version:5.4.1

Server OS version: windows 7 64-bit

Browser version: Chrome Version 59.0.3071.115 (Official Build) (64-bit)

Description of the problem including expected versus actual behavior:
In Tile Map with map type 'shaded geohash grid' and geocentorid active, when I trigger the 'Fit Data Bounds' event the map zooms in too much, leaving part of the grid outside the map's shown borders.
I believe the expected behavior should be zooming in to a zoom level which will display an area ~110% greater than the grid's area and by that leaving a small margin between the grid and the map's borders.
This behavior only occurs when geocentroid is active.

Steps to reproduce:

1. Create new Tile Map visualization
2. Choose geo_point field
3. Choose the time in the time picker.
4. Go to option tab and choose 'shaded geohash grid'
5. Press on apply changes
6. Press on Fit Data Bounds

Before Fit Data Bounds:

After Fit Data Bounds:

[OmKoren]

+1

[thomasneirynck]

This has been fixed with #12806