[FIXED] Stream's subscription propagation issue with gateways

When creating shadow subscriptions for import streams, we were
not invoking code for gateway subscription accounting, which means
that when the account (for leafnodes) was switched to interest
only, those shadow subscriptions were not sent.

Signed-off-by: Ivan Kozlovic <ivan@synadia.com>

test/leafnode_test.go

@@ -4087,3 +4087,120 @@ func TestLeafNodeAdvertiseInCluster(t *testing.T) {
 	s2.Shutdown()
 	expectNothing(t, lc)
 }
+
+func TestLeafNodeStreamAndShadowSubs(t *testing.T) {
+	conf1 := createConfFile(t, []byte(`
+		port: -1
+		system_account: SYS
+		accounts {
+			SYS {}
+			A: {
+				users: [{ user: a, password: pwd, permissions: {publish: [A.b.>]} }]
+				exports: [{ stream: A.b.>, accounts: [B] }]
+			},
+			B: {
+				users: [{ user: b, password: pwd, permissions: {subscribe: [ A.b.> ]}}]
+				imports: [{ stream: { account: A, subject: A.b.> } }]
+			}
+		}
+		gateway {
+			name: "A"
+			port: -1
+		}
+		leafnodes {
+			port: -1
+			authorization: {
+				users: [
+					{user: a, password: pwd, account: A}
+				]
+			}
+		}
+	`))
+	defer os.Remove(conf1)
+	s1, o1 := RunServerWithConfig(conf1)
+	defer s1.Shutdown()
+
+	conf2 := createConfFile(t, []byte(fmt.Sprintf(`
+		port: -1
+		system_account: SYS
+		accounts {
+			SYS {}
+			A: {
+				users: [{ user: a, password: pwd, permissions: {publish: [A.b.>]} }]
+				exports: [{ stream: A.b.>, accounts: [B] }]
+			},
+			B: {
+				users: [{ user: b, password: pwd, permissions: {subscribe: [ A.b.> ]}}]
+				imports: [{ stream: { account: A, subject: A.b.> } }]
+			}
+		}
+		gateway {
+			name: "B"
+			port: -1
+			gateways [
+				{
+					name: "A"
+					urls: ["nats://127.0.0.1:%d"]
+				}
+			]
+		}
+	`, o1.Gateway.Port)))
+	defer os.Remove(conf2)
+	s2, o2 := RunServerWithConfig(conf2)
+	defer s2.Shutdown()
+
+	waitForOutboundGateways(t, s1, 1, 2*time.Second)
+	waitForOutboundGateways(t, s2, 1, 2*time.Second)
+
+	nc, err := nats.Connect(fmt.Sprintf("nats://b:pwd@127.0.0.1:%d", o2.Port))
+	if err != nil {
+		t.Fatalf("Error on connect: %v", err)
+	}
+	defer nc.Close()
+
+	sub, err := nc.SubscribeSync("A.b.>")
+	if err != nil {
+		t.Fatalf("Error on subscibe: %v", err)
+	}
+	defer sub.Unsubscribe()
+
+	conf3 := createConfFile(t, []byte(fmt.Sprintf(`
+		port: -1
+		system_account: SYS
+		accounts: {
+			SYS {}
+			C: {
+				imports: [{ stream: { account: D, subject: b.> }, prefix: A }]
+			}
+			D: {
+				users: [{ user: d, password: pwd, permissions: {publish: [ b.> ]} }]
+				exports: [{ stream: b.>, accounts: [C] }]
+			}
+		}
+		leafnodes {
+			remotes [
+				{
+					url: "nats://a:pwd@127.0.0.1:%d"
+					account: C
+				}
+			]
+		}
+	`, o1.LeafNode.Port)))
+	defer os.Remove(conf3)
+	s3, o3 := RunServerWithConfig(conf3)
+	defer s3.Shutdown()
+
+	checkLeafNodeConnected(t, s1)
+	checkLeafNodeConnected(t, s3)
+
+	ncl, err := nats.Connect(fmt.Sprintf("nats://d:pwd@127.0.0.1:%d", o3.Port))
+	if err != nil {
+		t.Fatalf("Error connecting: %v", err)
+	}
+	defer ncl.Close()
+
+	ncl.Publish("b.c", []byte("test"))
+	if _, err := sub.NextMsg(time.Second); err != nil {
+		t.Fatalf("Did not receive message: %v", err)
+	}
+}