Remove manual source map composition as the compiler now does that natively

lib/gulp/index.js

@@ -44,8 +44,6 @@ module.exports = function(initOptions) {
   var PLUGIN_NAME = 'gulp-google-closure-compiler';
 
   var extraCommandArguments = initOptions ? initOptions.extraArguments : undefined;
-  var SourceMapGenerator = require('source-map').SourceMapGenerator;
-  var SourceMapConsumer = require('source-map').SourceMapConsumer;
   var applySourceMap = require('vinyl-sourcemaps-apply');
   var path = require('path');
 
@@ -175,21 +173,7 @@ module.exports = function(initOptions) {
 
         for (var i = 0; i < outputFiles.length; i++) {
           if (outputFiles[i].sourceMap) {
-            // Closure compiler does not compose source maps (use input source maps)
-            // We need to manually compose the maps so that we reference the original file
-            var generator = SourceMapGenerator.fromSourceMap(
-                new SourceMapConsumer(outputFiles[i].sourceMap));
-            outputFiles[i].sourceMap = undefined;
-
-            for (var j = 0; j < jsonFiles.length; j++) {
-              if (!jsonFiles[j].sourceMap) {
-                continue;
-              }
-              generator.applySourceMap(
-                  new SourceMapConsumer(jsonFiles[j].sourceMap),
-                  jsonFiles[j].path.substr(1));
-            }
-            applySourceMap(outputFiles[i], generator.toString());
+            applySourceMap(outputFiles[i], outputFiles[i].sourceMap);
           }
           this.push(outputFiles[i]);
         }

package.json

@@ -38,7 +38,6 @@
   "dependencies": {
     "chalk": "^1.0.0",
     "gulp-util": "^3.0.7",
-    "source-map": "^0.5.3",
     "vinyl-fs": "^2.2.1",
     "vinyl-sourcemaps-apply": "^0.2.0"
   },