avoid some redundant information in GeoSceneTexture::tileSize()
avoid some redundant information in GeoSceneTexture::tileSize()

TileId's mapThemeIdHash() isn't (and shouldn't) be used inside GeoSceneTexture since it represents redundant information to sourceDir().
Passing '0' as mapThemeIdHash makes this more clear.

Earthwings/marble,utkuaydin/marble,utkuaydin/marble,quannt24/marble,probonopd/marble,Earthwings/marble,rku/marble,rku/marble,David-Gil/marble-dev,oberluz/marble,rku/marble,David-Gil/marble-dev,oberluz/marble,utkuaydin/marble,utkuaydin/marble,AndreiDuma/marble,rku/marble,probonopd/marble,probonopd/marble,Earthwings/marble,tucnak/marble,tzapzoor/marble,tzapzoor/marble,adraghici/marble,David-Gil/marble-dev,probonopd/marble,AndreiDuma/marble,tzapzoor/marble,adraghici/marble,adraghici/marble,quannt24/marble,AndreiDuma/marble,utkuaydin/marble,tzapzoor/marble,tucnak/marble,adraghici/marble,probonopd/marble,oberluz/marble,oberluz/marble,tzapzoor/marble,David-Gil/marble-dev,quannt24/marble,David-Gil/marble-dev,tucnak/marble,AndreiDuma/marble,rku/marble,quannt24/marble,tucnak/marble,tzapzoor/marble,David-Gil/marble-dev,tucnak/marble,probonopd/marble,quannt24/marble,quannt24/marble,quannt24/marble,tzapzoor/marble,utkuaydin/marble,adraghici/marble,tucnak/marble,Earthwings/marble,rku/marble,probonopd/marble,Earthwings/marble,adraghici/marble,oberluz/marble,AndreiDuma/marble,Earthwings/marble,oberluz/marble,tucnak/marble,AndreiDuma/marble,tzapzoor/marble