Add non-zero ed check on Balances genesis

frame/balances/src/lib.rs

@@ -394,6 +394,10 @@ decl_storage! {
 		config(balances): Vec<(T::AccountId, T::Balance)>;
 		// ^^ begin, length, amount liquid at genesis
 		build(|config: &GenesisConfig<T, I>| {
+			assert!(
+				<T as Trait<I>>::ExistentialDeposit::get() > Zero::zero(),
+				"the existential deposit should be non-zero."
+			);
 			for (_, balance) in &config.balances {
 				assert!(
 					*balance >= <T as Trait<I>>::ExistentialDeposit::get(),

frame/balances/src/mock.rs

@@ -103,7 +103,7 @@ pub struct ExtBuilder {
 impl Default for ExtBuilder {
 	fn default() -> Self {
 		Self {
-			existential_deposit: 0,
+			existential_deposit: 1,
 			creation_fee: 0,
 			monied: false,
 		}