Use the webpack 2 chunk api

Call chunk.hasRuntime() instead of checking chunk.entry.

Author: brandondoran

lib/ChunkManifestPlugin.js

@@ -23,7 +23,7 @@ ChunkManifestPlugin.prototype.apply = function(compiler) {
         chunkManifest = [chunk].reduce(function registerChunk(manifest, c) {
           if(c.id in manifest) return manifest;
 
-          if(c.entry) {
+          if(c.hasRuntime()) {
             manifest[c.id] = undefined;
           } else {
             manifest[c.id] = mainTemplate.applyPluginsWaterfall("asset-path", filename, {