Support nullish coalescing with tree-shaking (#3548)

* Support nullish coalescing with tree-shaking, update acorn

* Use Node 14 image for CI tests

.circleci/config.yml

@@ -48,9 +48,9 @@ jobs:
       - run:
           name: Post REPL comment
           command: ./scripts/post-comment.js
-  node-v13-latest:
+  node-v14-latest:
     docker:
-      - image: lukastaegert/circleci-node-v13:latest
+      - image: rollupcabal/circleci-node-v14:latest
     steps:
       - checkout
       - restore_cache:
@@ -80,7 +80,7 @@ workflows:
           filters:
             tags:
               only: /.*/
-      - node-v13-latest:
+      - node-v14-latest:
           requires:
             - analysis
           filters:

LICENSE.md

@@ -82,33 +82,6 @@ Repository: https://github.com/acornjs/acorn-class-fields
 
 ---------------------------------------
 
-## acorn-export-ns-from
-License: MIT
-By: Adrian Heine
-Repository: https://github.com/acornjs/acorn-export-ns-from
-
-> Copyright (C) 2017-2018 by Adrian Heine
-> 
-> Permission is hereby granted, free of charge, to any person obtaining a copy
-> of this software and associated documentation files (the "Software"), to deal
-> in the Software without restriction, including without limitation the rights
-> to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-> copies of the Software, and to permit persons to whom the Software is
-> furnished to do so, subject to the following conditions:
-> 
-> The above copyright notice and this permission notice shall be included in
-> all copies or substantial portions of the Software.
-> 
-> THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-> IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-> FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-> AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-> LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-> OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-> THE SOFTWARE.
-
----------------------------------------
-
 ## acorn-import-meta
 License: MIT
 By: Adrian Heine