Don't compile Hermes-supported features with Babel (#1773)

* Don't transpile Hermes-supported features

* Disable the object spread plugin

We're using Hermes, and Hermes supports object spread.
We can remove this patch when we upgrade Expo because it'll be conditional there.

babel.config.js

@@ -8,6 +8,9 @@ module.exports = function (api) {
         {
           lazyImports: true,
           native: {
+            // We should be able to remove this after upgrading Expo
+            // to a version that includes https://github.com/expo/expo/pull/24672.
+            unstable_transformProfile: 'hermes-stable',
             // Disable ESM -> CJS compilation because Metro takes care of it.
             // However, we need it in Jest tests since those run without Metro.
             disableImportExportTransform: !isTestEnv,

patches/babel-preset-expo+9.5.2.patch

@@ -0,0 +1,14 @@
+diff --git a/node_modules/babel-preset-expo/index.js b/node_modules/babel-preset-expo/index.js
+index 2099ee3..2b9e092 100644
+--- a/node_modules/babel-preset-expo/index.js
++++ b/node_modules/babel-preset-expo/index.js
+@@ -105,7 +105,8 @@ module.exports = function (api, options = {}) {
+       ],
+     ],
+     plugins: [
+-      getObjectRestSpreadPlugin(),
++      // - dan: This will be disabled anyway when we upgrade Expo, but let's do it now.
++      // getObjectRestSpreadPlugin(),
+       ...extraPlugins,
+       getAliasPlugin(),
+       [require.resolve('@babel/plugin-proposal-decorators'), { legacy: true }],