fix case where no overrides exist

Author: benholloway

lib/inject/bower-files.js

@@ -156,12 +156,11 @@ function json(includeDev, context) {
   }
 
   function processOverrides(packages, overrides) {
-    return Object.keys(packages)
-      .reduce(reducePackages, {});
+    return overrides ? Object.keys(packages).reduce(reducePackages, {}) : packages;
 
     function reducePackages(result, packageName) {
       var item     = packages[packageName],
-          override = overrides[packageName + '.' + context] || overrides[packageName];
+          override = context && overrides[packageName + '.' + context] || overrides[packageName];
       result[packageName] = defaults({}, override, item);
       return result;
     }