Replace ErrorExit with log.Fatal in the mojom tool.

mojom/mojom_parser/fmt_cmd.go

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file contains fmtCmd which formats a .mojom file and outputs the
 // formatted mojom file to stdout.
 // The fmt command is invoked as follows:
 //
 //              mojom fmt [-w] <mojom_file>
 //
 //      If -w is specified and the formatted file is different from the original,
 //      the file is overwritten with the formatted version.
 package main
 
 import (
         "flag"
         "fmt"
         "io/ioutil"
+        "log"
         "mojom/mojom_parser/formatter"
         "os"
         "path/filepath"
 )
 
 // fmtCmd implements the fmt command for the mojom tool.
 // The slice of strings |args| is the list of arguments passed on the command
 // line starting with the program name and followed by the invoked command.
 func fmtCmd(args []string) {
         flagSet := flag.NewFlagSet("fmt", flag.ContinueOnError)
@@ skipping 16 matching lines @@
 
         inputFileName := flagSet.Arg(0)
         if inputFileName == "" {
                 fmt.Fprintln(os.Stderr, "No .mojom file given.")
                 printUsage()
                 os.Exit(1)
         }
 
         originalBytes, err := ioutil.ReadFile(inputFileName)
         if err != nil {
-                ErrorExit(err.Error())
+                log.Fatalln(err.Error())
         }
 
         original := string(originalBytes[:])
 
         var formatted string
         formatted, err = formatter.FormatMojom(inputFileName, original)
         if err != nil {
-                ErrorExit(err.Error())
+                log.Fatalln(err.Error())
         }
 
         if overwrite {
                 if formatted != original {
                         if err := ioutil.WriteFile(inputFileName, []byte(formatted), 0); err != nil {
-                                ErrorExit(err.Error())
+                                log.Fatalln(err.Error())
                         }
                 }
         } else {
                 fmt.Print(formatted)
         }
 }