refactor(staking): remove expected distribution keeper (backport #17261)

x/distribution/README.md

@@ -352,15 +352,22 @@ The transaction fails if the amount cannot be transferred from the sender to the
 
 ```go
 func (k Keeper) FundCommunityPool(ctx context.Context, amount sdk.Coins, sender sdk.AccAddress) error {
-    if err := k.bankKeeper.SendCoinsFromAccountToModule(ctx, sender, types.ModuleName, amount); err != nil {
-        return err
-    }
+  if err := k.bankKeeper.SendCoinsFromAccountToModule(ctx, sender, types.ModuleName, amount); err != nil {
+    return err
+  }
 
-	feePool := k.GetFeePool(ctx)
-	feePool.CommunityPool = feePool.CommunityPool.Add(sdk.NewDecCoinsFromCoins(amount...)...)
-	k.SetFeePool(ctx, feePool)
+  feePool, err := k.FeePool.Get(ctx)
+  if err != nil {
+    return err
+  }
+
+  feePool.CommunityPool = feePool.CommunityPool.Add(sdk.NewDecCoinsFromCoins(amount...)...)
+
+  if err := k.FeePool.Set(ctx, feePool); err != nil {
+    return err
+  }
 
-	return nil
+  return nil
 }
 ```
 

x/staking/types/expected_keepers.go

@@ -9,12 +9,6 @@ import (
 	sdk "github.com/cosmos/cosmos-sdk/types"
 )
 
-// DistributionKeeper expected distribution keeper (noalias)
-type DistributionKeeper interface {
-	GetFeePoolCommunityCoins(ctx context.Context) sdk.DecCoins
-	GetValidatorOutstandingRewardsCoins(ctx context.Context, val sdk.ValAddress) sdk.DecCoins
-}
-
 // AccountKeeper defines the expected account keeper (noalias)
 type AccountKeeper interface {
 	AddressCodec() address.Codec