Remove unnecessary returns in asyncToGenerator helper

packages/babel-core/test/fixtures/transformation/misc/regression-2892/expected.js

@@ -46,7 +46,7 @@ var foo = function () {
   };
 }();
 
-function _asyncToGenerator(fn) { return function () { var gen = fn.apply(this, arguments); return new Promise(function (resolve, reject) { function step(key, arg) { try { var info = gen[key](arg); var value = info.value; } catch (error) { reject(error); return; } if (info.done) { resolve(value); } else { return Promise.resolve(value).then(function (value) { step("next", value); }, function (err) { step("throw", err); }); } } return step("next"); }); }; }
+function _asyncToGenerator(fn) { return function () { var gen = fn.apply(this, arguments); return new Promise(function (resolve, reject) { function step(key, arg) { try { var info = gen[key](arg); var value = info.value; } catch (error) { reject(error); return; } if (info.done) { resolve(value); } else { Promise.resolve(value).then(function (value) { step("next", value); }, function (err) { step("throw", err); }); } } step("next"); }); }; }
 
 function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
 

packages/babel-helpers/src/helpers.js

@@ -230,15 +230,15 @@ helpers.asyncToGenerator = template(`
           if (info.done) {
             resolve(value);
           } else {
-            return Promise.resolve(value).then(function (value) {
+            Promise.resolve(value).then(function (value) {
               step("next", value);
             }, function (err) {
               step("throw", err);
             });
           }
         }
 
-        return step("next");
+        step("next");
       });
     };
   })