Merge branch 'ee-webpack-backport' into 'master'

Backport webpack.config.js changes from EE

See merge request gitlab-org/gitlab-ce!17185

config/webpack.config.js

@@ -27,11 +27,11 @@ var pageEntries = glob.sync('pages/**/index.js', { cwd: path.join(ROOT_PATH, 'ap
 
 // filter out entries currently imported dynamically in dispatcher.js
 var dispatcher = fs.readFileSync(path.join(ROOT_PATH, 'app/assets/javascripts/dispatcher.js')).toString();
-var dispatcherChunks = dispatcher.match(/(?!import\('.\/)pages\/[^']+/g);
+var dispatcherChunks = dispatcher.match(/(?!import\(')\.\/pages\/[^']+/g);
 
 pageEntries.forEach(( path ) => {
   let chunkPath = path.replace(/\/index\.js$/, '');
-  if (!dispatcherChunks.includes(chunkPath)) {
+  if (!dispatcherChunks.includes('./' + chunkPath)) {
     let chunkName = chunkPath.replace(/\//g, '.');
     autoEntries[chunkName] = './' + path;
   }