removed dead code, cleanup

index.js

@@ -12,7 +12,6 @@ var OrderUndefinedError = require("./OrderUndefinedError");
 var loaderUtils = require("loader-utils");
 var validateOptions = require('schema-utils');
 var path = require('path');
-var OriginalSource = require("webpack-sources").OriginalSource;
 
 var NS = fs.realpathSync(__dirname);
 
@@ -277,7 +276,6 @@ ExtractTextPlugin.prototype.apply = function(compiler) {
 					if(meta && (!meta.options.id || meta.options.id === id)) {
 						var wasExtracted = Array.isArray(meta.content);
 						if(shouldExtract !== wasExtracted) {
-							// don't remove
 							var newModule = new NormalModule(
 								module.request,
 								module.userRequest,
@@ -287,6 +285,7 @@ ExtractTextPlugin.prototype.apply = function(compiler) {
 								module.parser
 							);
 							newModule[NS + "/extract"] = shouldExtract; // eslint-disable-line no-path-concat
+							// build a new module and save result to extracted compilations
 							compilation.buildModule(newModule, false, newModule, null, function(err) {
 								if(err) {
 									compilation.errors.push(err);
@@ -360,7 +359,7 @@ ExtractTextPlugin.prototype.apply = function(compiler) {
 					newModule._source = data.module._source;
 					data.chunks.forEach(function (chunk) {
 						chunk.removeModule(data.moduleToRemove);
-						var deps = data.moduleToRemove.dependencies.slice();
+						var deps = data.moduleToRemove.dependencies;
 						deps.forEach(d => {
 							chunk.removeModule(d.module);
 						});