enable `go vet`

.travis.yml

@@ -16,7 +16,7 @@ before_script:
   - gofmt -l -w .
   - goimports -l -w .
   - golint .
-  # - go vet ./...
+  - go vet ./...
   # - go test -race ./...
 script:
   - ./gocoverage.sh

event/profile.tmp

+mode: count
+github.com/ethereum/go-ethereum/event/event.go:41.66,45.17 4 1005
+github.com/ethereum/go-ethereum/event/event.go:63.2,63.12 1 1004
+github.com/ethereum/go-ethereum/event/event.go:45.17,47.3 1 1
+github.com/ethereum/go-ethereum/event/event.go:47.3,48.22 1 1004
+github.com/ethereum/go-ethereum/event/event.go:51.3,51.27 1 1004
+github.com/ethereum/go-ethereum/event/event.go:48.22,50.4 1 5
+github.com/ethereum/go-ethereum/event/event.go:51.27,54.32 3 1006
+github.com/ethereum/go-ethereum/event/event.go:57.4,60.25 4 1005
+github.com/ethereum/go-ethereum/event/event.go:54.32,56.5 1 1
+github.com/ethereum/go-ethereum/event/event.go:68.48,71.17 3 3513
+github.com/ethereum/go-ethereum/event/event.go:75.2,77.27 3 3511
+github.com/ethereum/go-ethereum/event/event.go:80.2,80.12 1 3509
+github.com/ethereum/go-ethereum/event/event.go:71.17,74.3 2 2
+github.com/ethereum/go-ethereum/event/event.go:77.27,79.3 1 2576
+github.com/ethereum/go-ethereum/event/event.go:86.28,88.32 2 5
+github.com/ethereum/go-ethereum/event/event.go:93.2,95.20 3 5
+github.com/ethereum/go-ethereum/event/event.go:88.32,89.28 1 3
+github.com/ethereum/go-ethereum/event/event.go:89.28,91.4 1 3
+github.com/ethereum/go-ethereum/event/event.go:98.36,100.34 2 1001
+github.com/ethereum/go-ethereum/event/event.go:109.2,109.22 1 1001
+github.com/ethereum/go-ethereum/event/event.go:100.34,101.37 1 1001
+github.com/ethereum/go-ethereum/event/event.go:101.37,102.22 1 1001
+github.com/ethereum/go-ethereum/event/event.go:102.22,104.5 1 2
+github.com/ethereum/go-ethereum/event/event.go:104.5,106.5 1 999
+github.com/ethereum/go-ethereum/event/event.go:112.46,113.26 1 2007
+github.com/ethereum/go-ethereum/event/event.go:118.2,118.11 1 1005
+github.com/ethereum/go-ethereum/event/event.go:113.26,114.16 1 181499
+github.com/ethereum/go-ethereum/event/event.go:114.16,116.4 1 1002
+github.com/ethereum/go-ethereum/event/event.go:121.52,126.2 4 999
+github.com/ethereum/go-ethereum/event/event.go:142.35,150.2 2 1005
+github.com/ethereum/go-ethereum/event/event.go:152.44,154.2 1 1003
+github.com/ethereum/go-ethereum/event/event.go:156.32,159.2 2 1001
+github.com/ethereum/go-ethereum/event/event.go:161.30,164.14 3 1004
+github.com/ethereum/go-ethereum/event/event.go:167.2,173.19 6 1003
+github.com/ethereum/go-ethereum/event/event.go:164.14,166.3 1 1
+github.com/ethereum/go-ethereum/event/event.go:176.42,178.9 2 2575
+github.com/ethereum/go-ethereum/event/event.go:182.2,182.20 1 2575
+github.com/ethereum/go-ethereum/event/event.go:179.2,179.21 0 1004
+github.com/ethereum/go-ethereum/event/event.go:180.2,180.19 0 1571