Patch for Osmosis v6.

We basically say that if we are past the upgrade height, do correct logic (from before).
If we are not, just always panic with the same message we used to get.

Author: ValarDragon

modules/core/02-client/keeper/keeper.go

@@ -307,10 +307,19 @@ func (k Keeper) ValidateSelfClient(ctx sdk.Context, clientState exported.ClientS
 		return sdkerrors.Wrapf(types.ErrInvalidClient, "trust-level invalid: %v", err)
 	}
 
-	expectedUbdPeriod := k.stakingKeeper.UnbondingTime(ctx)
-	if expectedUbdPeriod != tmClient.UnbondingPeriod {
-		return sdkerrors.Wrapf(types.ErrInvalidClient, "invalid unbonding period. expected: %s, got: %s",
-			expectedUbdPeriod, tmClient.UnbondingPeriod)
+	// Osmosis v6 patch. If height > 300, do correct logic on fixed app.go
+	// Prior to fork height, we panic with the same error we were getting before.
+	if ctx.BlockHeight() > 300 {
+		expectedUbdPeriod := k.stakingKeeper.UnbondingTime(ctx)
+		if expectedUbdPeriod != tmClient.UnbondingPeriod {
+			return sdkerrors.Wrapf(types.ErrInvalidClient, "invalid unbonding period. expected: %s, got: %s",
+				expectedUbdPeriod, tmClient.UnbondingPeriod)
+		}
+	} else {
+		// Do the old panic, of just saying its not found.
+		// Panic came from here: https://github.com/cosmos/cosmos-sdk/blob/d0f64dff2cc370b876c82244bd46b61872d6ffa5/x/params/types/subspace.go#L170
+		key := "UnbondingTime"
+		panic(fmt.Sprintf("parameter %s not registered", key))
 	}
 
 	if tmClient.UnbondingPeriod < tmClient.TrustingPeriod {