Community pool spend proposal (#4329)

Implement the "CommunityPoolSpendProposal" as described in Cosmos Hub proposal 7.

Also a useful test of Git flow for merging features passed in governance proposals.

simapp/app.go

@@ -159,7 +159,8 @@ func NewSimApp(logger log.Logger, db dbm.DB, traceStore io.Writer, loadLatest bo
 	// register the proposal types
 	govRouter := gov.NewRouter()
 	govRouter.AddRoute(gov.RouterKey, gov.ProposalHandler).
-		AddRoute(params.RouterKey, params.NewParamChangeProposalHandler(app.paramsKeeper))
+		AddRoute(params.RouterKey, params.NewParamChangeProposalHandler(app.paramsKeeper)).
+		AddRoute(distr.RouterKey, distr.NewCommunityPoolSpendProposalHandler(app.distrKeeper))
 	app.govKeeper = gov.NewKeeper(app.cdc, app.keyGov, app.paramsKeeper, govSubspace,
 		app.bankKeeper, &stakingKeeper, gov.DefaultCodespace, govRouter)
 

simapp/sim_test.go

@@ -301,6 +301,7 @@ func testAndRunTxs(app *SimApp) []simulation.WeightedOperation {
 		{50, distrsim.SimulateMsgWithdrawDelegatorReward(app.accountKeeper, app.distrKeeper)},
 		{50, distrsim.SimulateMsgWithdrawValidatorCommission(app.accountKeeper, app.distrKeeper)},
 		{5, govsim.SimulateSubmittingVotingAndSlashingForProposal(app.govKeeper, govsim.SimulateTextProposalContent)},
+		{5, govsim.SimulateSubmittingVotingAndSlashingForProposal(app.govKeeper, distrsim.SimulateCommunityPoolSpendProposalContent(app.distrKeeper))},
 		{5, govsim.SimulateSubmittingVotingAndSlashingForProposal(app.govKeeper, paramsim.SimulateParamChangeProposalContent)},
 		{100, govsim.SimulateMsgDeposit(app.govKeeper)},
 		{100, stakingsim.SimulateMsgCreateValidator(app.accountKeeper, app.stakingKeeper)},