refactor: active channel key format (cosmos#823)

## Description

Updating the store key format for active channels based on @AdityaSripal comment. 

closes: [Adityas comment](cosmos#814 (review))

---

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- [ ] Targeted PR against correct branch (see [CONTRIBUTING.md](https://github.com/cosmos/ibc-go/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
- [ ] Code follows the [module structure standards](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules/structure.md).
- [ ] Wrote unit and integration [tests](https://github.com/cosmos/ibc-go/blob/master/CONTRIBUTING.md#testing)
- [ ] Updated relevant documentation (`docs/`) or specification (`x/<module>/spec/`)
- [ ] Added relevant `godoc` [comments](https://blog.golang.org/godoc-documenting-go-code).
- [ ] Added a relevant changelog entry to the `Unreleased` section in `CHANGELOG.md`
- [ ] Re-reviewed `Files changed` in the Github PR explorer
- [ ] Review `Codecov Report` in the comment section below once CI passes

modules/apps/27-interchain-accounts/controller/keeper/keeper.go

@@ -105,7 +105,7 @@ func (k Keeper) ClaimCapability(ctx sdk.Context, cap *capabilitytypes.Capability
 // GetActiveChannelID retrieves the active channelID from the store, keyed by the provided connectionID and portID
 func (k Keeper) GetActiveChannelID(ctx sdk.Context, connectionID, portID string) (string, bool) {
 	store := ctx.KVStore(k.storeKey)
-	key := icatypes.KeyActiveChannel(connectionID, portID)
+	key := icatypes.KeyActiveChannel(portID, connectionID)
 
 	if !store.Has(key) {
 		return "", false
@@ -141,8 +141,8 @@ func (k Keeper) GetAllActiveChannels(ctx sdk.Context) []icatypes.ActiveChannel {
 		keySplit := strings.Split(string(iterator.Key()), "/")
 
 		ch := icatypes.ActiveChannel{
-			ConnectionId: keySplit[1],
-			PortId:       keySplit[2],
+			ConnectionId: keySplit[2],
+			PortId:       keySplit[1],
 			ChannelId:    string(iterator.Value()),
 		}
 
@@ -155,7 +155,7 @@ func (k Keeper) GetAllActiveChannels(ctx sdk.Context) []icatypes.ActiveChannel {
 // SetActiveChannelID stores the active channelID, keyed by the provided connectionID and portID
 func (k Keeper) SetActiveChannelID(ctx sdk.Context, connectionID, portID, channelID string) {
 	store := ctx.KVStore(k.storeKey)
-	store.Set(icatypes.KeyActiveChannel(connectionID, portID), []byte(channelID))
+	store.Set(icatypes.KeyActiveChannel(portID, connectionID), []byte(channelID))
 }
 
 // IsActiveChannel returns true if there exists an active channel for the provided connectionID and portID, otherwise false

modules/apps/27-interchain-accounts/host/keeper/keeper.go

@@ -94,7 +94,7 @@ func (k Keeper) ClaimCapability(ctx sdk.Context, cap *capabilitytypes.Capability
 // GetActiveChannelID retrieves the active channelID from the store keyed by the provided connectionID and portID
 func (k Keeper) GetActiveChannelID(ctx sdk.Context, connectionID, portID string) (string, bool) {
 	store := ctx.KVStore(k.storeKey)
-	key := icatypes.KeyActiveChannel(connectionID, portID)
+	key := icatypes.KeyActiveChannel(portID, connectionID)
 
 	if !store.Has(key) {
 		return "", false
@@ -130,8 +130,8 @@ func (k Keeper) GetAllActiveChannels(ctx sdk.Context) []icatypes.ActiveChannel {
 		keySplit := strings.Split(string(iterator.Key()), "/")
 
 		ch := icatypes.ActiveChannel{
-			ConnectionId: keySplit[1],
-			PortId:       keySplit[2],
+			ConnectionId: keySplit[2],
+			PortId:       keySplit[1],
 			ChannelId:    string(iterator.Value()),
 		}
 
@@ -144,7 +144,7 @@ func (k Keeper) GetAllActiveChannels(ctx sdk.Context) []icatypes.ActiveChannel {
 // SetActiveChannelID stores the active channelID, keyed by the provided connectionID and portID
 func (k Keeper) SetActiveChannelID(ctx sdk.Context, connectionID, portID, channelID string) {
 	store := ctx.KVStore(k.storeKey)
-	store.Set(icatypes.KeyActiveChannel(connectionID, portID), []byte(channelID))
+	store.Set(icatypes.KeyActiveChannel(portID, connectionID), []byte(channelID))
 }
 
 // IsActiveChannel returns true if there exists an active channel for the provided connectionID and portID, otherwise false

modules/apps/27-interchain-accounts/types/keys.go

@@ -39,8 +39,8 @@ var (
 )
 
 // KeyActiveChannel creates and returns a new key used for active channels store operations
-func KeyActiveChannel(connectionID, portID string) []byte {
-	return []byte(fmt.Sprintf("%s/%s/%s", ActiveChannelKeyPrefix, connectionID, portID))
+func KeyActiveChannel(portID, connectionID string) []byte {
+	return []byte(fmt.Sprintf("%s/%s/%s", ActiveChannelKeyPrefix, portID, connectionID))
 }
 
 // KeyOwnerAccount creates and returns a new key used for interchain account store operations

modules/apps/27-interchain-accounts/types/keys_test.go

@@ -5,8 +5,8 @@ import (
 )
 
 func (suite *TypesTestSuite) TestKeyActiveChannel() {
-	key := types.KeyActiveChannel("connection-id", "port-id")
-	suite.Require().Equal("activeChannel/connection-id/port-id", string(key))
+	key := types.KeyActiveChannel("port-id", "connection-id")
+	suite.Require().Equal("activeChannel/port-id/connection-id", string(key))
 }
 
 func (suite *TypesTestSuite) TestKeyOwnerAccount() {