Replace ErrorExit with log.Fatal in the mojom tool.

mojom/mojom_parser/mojom_main.go

Index: mojom/mojom_parser/mojom_main.go
diff --git a/mojom/mojom_parser/mojom_main.go b/mojom/mojom_parser/mojom_main.go
index 7bbdff7893e34abea4a3247aa619e514966eb5c1..05454635503b6bd2f1ec4fc5e38d10232c521e07 100644
--- a/mojom/mojom_parser/mojom_main.go
+++ b/mojom/mojom_parser/mojom_main.go
@@ -8,6 +8,7 @@ import (
 	"bytes"
 	"flag"
 	"fmt"
+	"log"
 	"os"
 )
 
@@ -25,6 +26,7 @@ import (
 //	For further information about each command, see the file named
 //	<command>_cmd.go for example "parse_cmd.go" and "fmt_cmd.go".
 func main() {
+	log.SetFlags(0)
 	checkVersion(os.Args)
 	commands := NewCommandSet()
 	commands.AddCommand("parse", parseCmd, "Parses mojom files.")
@@ -33,11 +35,6 @@ func main() {
 	commands.RunCommand(os.Args)
 }
 
-func ErrorExit(message string) {
-	fmt.Fprintf(os.Stderr, "%s\n", message)
-	os.Exit(1)
-}
-
 type command struct {
 	Name string
 	Func func([]string)