cmd/go: enable tests of vet tool

    
    Since gofrontend does have the vet tool now, we can test it.
    
    Reviewed-on: https://go-review.googlesource.com/111095

From-SVN: r259919

gcc/go/gofrontend/MERGE

-bf6f714559bd7b27b7686811aaf0f6e8e7f1c0d5
+12325f36d965e2ac3a4cbf787472ce24923327da
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

libgo/go/cmd/go/go_test.go

@@ -3221,7 +3221,6 @@ func TestGoGetInternalWildcard(t *testing.T) {
 }
 
 func TestGoVetWithExternalTests(t *testing.T) {
-	skipIfGccgo(t, "gccgo does not have vet")
 	tg := testgo(t)
 	defer tg.cleanup()
 	tg.makeTempdir()
@@ -3231,7 +3230,6 @@ func TestGoVetWithExternalTests(t *testing.T) {
 }
 
 func TestGoVetWithTags(t *testing.T) {
-	skipIfGccgo(t, "gccgo does not have vet")
 	tg := testgo(t)
 	defer tg.cleanup()
 	tg.makeTempdir()
@@ -3241,7 +3239,6 @@ func TestGoVetWithTags(t *testing.T) {
 }
 
 func TestGoVetWithFlagsOn(t *testing.T) {
-	skipIfGccgo(t, "gccgo does not have vet")
 	tg := testgo(t)
 	defer tg.cleanup()
 	tg.makeTempdir()
@@ -3251,7 +3248,6 @@ func TestGoVetWithFlagsOn(t *testing.T) {
 }
 
 func TestGoVetWithFlagsOff(t *testing.T) {
-	skipIfGccgo(t, "gccgo does not have vet")
 	tg := testgo(t)
 	defer tg.cleanup()
 	tg.makeTempdir()