runtime/race: fix test driver

At some point it silently stopped recognizing test output.
Meanwhile two tests degraded...

Change-Id: I90a0325fc9aaa16c3ef16b9c4c642581da2bb10c
Reviewed-on: https://go-review.googlesource.com/11416Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/runtime/race/race_test.go

@@ -36,7 +36,7 @@ var (
 
 const (
 	visibleLen = 40
-	testPrefix = "=== RUN Test"
+	testPrefix = "=== RUN   Test"
 )
 
 func TestRace(t *testing.T) {
@@ -63,6 +63,9 @@ func TestRace(t *testing.T) {
 		}
 	}
 
+	if totalTests == 0 {
+		t.Fatalf("failed to parse test output")
+	}
 	fmt.Printf("\nPassed %d of %d tests (%.02f%%, %d+, %d-)\n",
 		passedTests, totalTests, 100*float64(passedTests)/float64(totalTests), falsePos, falseNeg)
 	fmt.Printf("%d expected failures (%d has not fail)\n", failingPos+failingNeg, failingNeg)

src/runtime/race/testdata/mop_test.go

@@ -1598,7 +1598,7 @@ func TestRaceSliceSlice(t *testing.T) {
 	<-c
 }
 
-func TestRaceSliceSlice2(t *testing.T) {
+func TestRaceSliceSlice2Failing(t *testing.T) {
 	c := make(chan bool, 1)
 	x := make([]int, 10)
 	i := 2
@@ -1610,7 +1610,7 @@ func TestRaceSliceSlice2(t *testing.T) {
 	<-c
 }
 
-func TestRaceSliceString(t *testing.T) {
+func TestRaceSliceStringFailing(t *testing.T) {
 	c := make(chan bool, 1)
 	x := "hello"
 	go func() {