DevTools: dtrun CLI helper

third_party/WebKit/Source/devtools/scripts/devtools_run/devtools_run_cli

+#!/usr/bin/env node
+
+// 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.
+
+var childProcess = require('child_process');
+var fs = require('fs');
+var path = require('path');
+var shell = require('child_process').execSync;
+
+var repoRootPath;
+try {
+  repoRootPath = shellOutput('git rev-parse --show-toplevel');
+} catch (error) {
+  console.log('ERROR: cannot use dtrun outside of chromium repo');
+  process.exit(1);
+}
+
+var devtoolsPath = path.join(repoRootPath, 'third_party', 'WebKit', 'Source', 'devtools');
+
+if (!isDir(devtoolsPath)) {
+  console.log('ERROR: cannot use dtrun outside of chromium repo');
+  process.exit(1);
+}
+
+var npmPath = shellOutput('which npm');
+var args = ['run'];
+if (process.argv.length > 2) {
+  args.push(process.argv[2]);
+  args.push('--');
+  args = args.concat(process.argv.slice(3));
+}
+var child = childProcess.spawn(npmPath, args, {
+  cwd: devtoolsPath,
+  stdio: 'inherit',
+});
+
+function shellOutput(command) {
+  return shell(command).toString().trim();
+}
+
+function isDir(path) {
+  try {
+    return fs.statSync(path).isDirectory();
+  } catch (error) {
+    return false;
+  }
+}