fix eslint config (#1462)

* update to bring in `eslint:recommended` as base config

.eslintrc.js

@@ -1,9 +1,10 @@
 module.exports = {
   // start with google standard style
   //     https://github.com/google/eslint-config-google/blob/master/index.js
-  "extends": "google",
+  "extends": ["eslint:recommended", "google"],
   "env": {
-    "node": true
+    "node": true,
+    "es6": true
   },
   "rules": {
     // 2 == error, 1 == warning, 0 == off
@@ -16,6 +17,9 @@ module.exports = {
       "ignoreUrls": true,
       "tabWidth": 2
     }],
+    "no-empty": [2, {
+      "allowEmptyCatch": true
+    }],
     "no-implicit-coercion": [2, {
       "boolean": false,
       "number": true,

lighthouse-cli/performance-experiment/report/injected-script.js

@@ -15,7 +15,7 @@
  * limitations under the License.
  */
 
-/* global window, document, location */
+/* global window, document, location, fetch */
 
 'use strict';
 

lighthouse-cli/test/fixtures/static-server.js

@@ -16,6 +16,8 @@
  */
 'use strict';
 
+/* eslint-disable no-console */
+
 const http = require('http');
 const path = require('path');
 const fs = require('fs');

lighthouse-cli/test/smokehouse/smokehouse.js

@@ -17,6 +17,8 @@
  */
 'use strict';
 
+/* eslint-disable no-console */
+
 const path = require('path');
 const spawnSync = require('child_process').spawnSync;
 const yargs = require('yargs');

lighthouse-core/gather/driver.js

@@ -739,6 +739,7 @@ class Driver {
  * @return {function(...*): *} A wrapper around the original function.
  */
 function captureJSCallUsage(funcRef, set) {
+  /* global window */
   const __nativeError = window.__nativeError || Error;
   const originalFunc = funcRef;
   const originalPrepareStackTrace = __nativeError.prepareStackTrace;

lighthouse-core/index.js

@@ -19,6 +19,7 @@
 
 const environment = require('../lighthouse-core/lib/environment');
 if (!environment.checkNodeCompatibility()) {
+  // eslint-disable-next-line no-console
   console.warn('Compatibility error', 'Lighthouse requires node 5+ or 4 with --harmony');
   process.exit(1);
 }

lighthouse-core/lib/console-quieter.js

@@ -17,6 +17,8 @@
 
 'use strict';
 
+/* eslint-disable no-console */
+
 const log = require('./log.js');
 
 class ConsoleQuieter {

lighthouse-core/scripts/build-traceviewer-module.js

@@ -21,6 +21,8 @@
  */
 'use strict';
 
+/* eslint-disable no-console */
+
 const fs = require('fs');
 const path = require('path');
 const jsdom = require('jsdom');

lighthouse-extension/app/src/chromereload.js

@@ -17,6 +17,8 @@
 
 'use strict';
 
+/* eslint-disable no-console */
+
 // Reload client for Chrome Apps & Extensions.
 // The reload client has a compatibility with livereload.
 // WARNING: only supports reload command.

lighthouse-extension/app/src/lighthouse-background.js

@@ -280,6 +280,7 @@ window.isRunning = function() {
 if (window.chrome && chrome.runtime) {
   chrome.runtime.onInstalled.addListener(details => {
     if (details.previousVersion) {
+      // eslint-disable-next-line no-console
       console.log('previousVersion', details.previousVersion);
     }
   });

lighthouse-viewer/app/src/lighthouse-report-viewer.js

@@ -370,11 +370,12 @@ class LighthouseViewerReport {
       case 'print':
         window.print();
         break;
-      case 'save-json':
+      case 'save-json': {
         const jsonStr = JSON.stringify(this.json, null, 2);
         this._saveFile(new Blob([jsonStr], {type: 'application/json'}));
         break;
-      case 'save-html':
+      }
+      case 'save-html': {
         const reportGenerator = new ReportGenerator();
         try {
           const htmlStr = reportGenerator.generateHTML(this.json, 'cli');
@@ -383,6 +384,7 @@ class LighthouseViewerReport {
           logger.error('Could not export as HTML.');
         }
         break;
+      }
     }
 
     this.closeExportDropdown();

lighthouse-viewer/app/src/logger.js

@@ -17,6 +17,8 @@
 
 'use strict';
 
+/* eslint-disable no-console */
+
 /**
  * Logs messages via a UI butter.
  * @class