WebUI: Experimenting with ESLint, WIP.

chrome/browser/resources/gulpfile.js

+const eslint = require('eslint');
+const gulp = require('gulp');
+const nopt = require('nopt');
+
+gulp.task('lint', () => {
+  const options = nopt({
+    'filter': [String, null],
+    'fix': [Boolean, null],
+  });
+  const srcPattern = options.filter ? `${options.filter}/**/*.js` : '**/*.js';
+
+  const CLIEngine = eslint.CLIEngine;
+  const cli = new CLIEngine({
+    fix: options.fix || false,
+  });
+  const report = cli.executeOnFiles([srcPattern]);
+  const formatter = cli.getFormatter();
+  console.log(formatter(report.results));
+
+  if (options.fix)
+    CLIEngine.outputFixes(report);
+});