Make dry grass spread on default:dirt again

[paramat]

Possibly attends to #2684

Commit c32b8ad possibly went too far in removing dry grass spreading behaviour in old savanna areas. This PR intends to restore dry grass spreading behaviour in the old savanna areas that use default:dirt and default:dirt_with_dry_grass.

Intentions:

• A default:dry_grass plant placed on default:dirt should eventually turn the default:dirt into default:dirt_with_dry_grass.
• default:dirt_with_dry_grass placed next to default:dirt should eventually turn the default:dirt into default:dirt_with_dry_grass.

Not yet tested. @Montandalar please test this. I will test when i have time.

[Montandalar]

Grass spread from dirt_with_dry_grass to default:dirt, but not from dry_dirt_with_dry_grass to default dirt. I had to add dry_dirt_with_dry_grass to have spreading_dirt_type = 1 as a group as well (see my branch).

Paramat's branch - no growth from dry dirt:

My branch - growth from dry dirt as well:

[paramat]

Thanks.

I had to add dry_dirt_with_dry_grass to have spreading_dirt_type = 1 as a group as well

Spreading from default:dry_dirt_with_dry_grass to default:dirt is not essential, as that combination is rare and this PR intends to restore spreading behaviour in old savanna areas.
Making default:dry_dirt_with_dry_grass a 'spreading_dirt_type' is unsuitable as it is not meant to spread.
So i prefer to leave this PR as it is. I will test it soon.

[paramat]

Tested and fine. I consider this mergeable.

Also tested that covered grasses are removed as expected:

[paramat]

Maybe merge for 5.3.0? Not high priority though.

[Montandalar]

Whether upstream considers it important or not, players on LinuxForks are looking forward to it being in 5.3.On 16 Jun. 2020 11:53, Paramat <notifications@github.com> wrote: Maybe merge for 5.3.0? Not high priority though. —You are receiving this because you were mentioned.Reply to this email directly, view it on GitHub, or unsubscribe.

[sfan5]

Looks good.
I am also fine with merging this in feature freeze.