Define default value for vars shadowing params (#11307)

* Define default value for vars shadowing params

* Remove from package.json

* Only convert traverse the params if needed

This prevents this plugin from running after the destructuring
transform, which causes #11256

* Review

* Review

* Update packages/babel-plugin-transform-parameters/src/params.js [skip ci]

Co-Authored-By: Brian Ng <bng412@gmail.com>

Co-authored-by: Brian Ng <bng412@gmail.com>

packages/babel-plugin-transform-parameters/package.json

@@ -9,7 +9,6 @@
   },
   "main": "lib/index.js",
   "dependencies": {
-    "@babel/helper-call-delegate": "^7.8.7",
     "@babel/helper-get-function-arity": "^7.8.3",
     "@babel/helper-plugin-utils": "^7.8.3"
   },