chore(build): rename .es6 files to .js

Change es6 source files in npm distribution to use .js extensions.

Closes #2447

tools/broccoli/traceur/index.ts

@@ -13,7 +13,7 @@ let xtend = require('xtend');
 class DiffingTraceurCompiler implements DiffingBroccoliPlugin {
   constructor(public inputPath: string, public cachePath: string, public options) {}
 
-  static includeExtensions = ['.js', '.es6', '.cjs'];
+  static includeExtensions = ['.js', '.cjs'];
 
   rebuild(treeDiff: DiffResult) {
     treeDiff.addedPaths.concat(treeDiff.changedPaths)

tools/broccoli/trees/browser_tree.ts

@@ -64,7 +64,7 @@ module.exports = function makeBrowserTree(options, destinationPath) {
 
   // Use Traceur to transpile *.js sources to ES6
   var traceurTree = transpileWithTraceur(modulesTree, {
-    destExtension: '.es6',
+    destExtension: '.js',
     destSourceMapExtension: '.map',
     traceurOptions: {
       sourceMaps: true,
@@ -93,7 +93,6 @@ module.exports = function makeBrowserTree(options, destinationPath) {
     sourceRoot: '.',
     target: 'ES6'
   });
-  typescriptTree = stew.rename(typescriptTree, '.js', '.es6');
 
   var es6Tree = mergeTrees([traceurTree, typescriptTree]);
 

tools/build/es5build.js

@@ -46,11 +46,8 @@ if (!module.parent) {
 }
 
 function run(config) {
-  var src = ['!node_modules', '!node_modules/**', './**/*.es6'];
+  var src = ['!node_modules', '!node_modules/**', './**/*.js'];
   return gulp.src(src, {cwd: config.src})
-    .pipe(rename(function(file) {
-      file.extname = file.extname.replace('.es6', '.js');
-    }))
     // TODO(tbosch): Using sourcemaps.init({loadMaps:true}) does not combine
     // the sourcemaps correctly!
     .pipe(sourcemaps.init())