FRE-600: Fix code review blockers

- Consolidated duplicate UndoManagers to single instance
- Fixed connection promise to only resolve on 'connected' status
- Fixed WebSocketProvider import (WebsocketProvider)
- Added proper doc.destroy() cleanup
- Renamed isPresenceInitialized property to avoid conflict

Co-Authored-By: Paperclip <noreply@paperclip.ing>

node_modules/isomorphic.js/iso.js

@@ -0,0 +1,18 @@
+
+const isNode = typeof process !== 'undefined' && process.release && /node|io\.js/.test(process.release.name)
+
+const isoBrowser = require('./browser.js')
+
+const perf = isNode ? require('perf_hooks').performance : isoBrowser.performance
+const nodeCrypto = isNode ? require('crypto') : null
+
+/**
+ * @type {function(number):ArrayBuffer}
+ */
+const cryptoRandomBuffer = nodeCrypto
+  // node
+  ? len => nodeCrypto.randomBytes(len).buffer
+  : isoBrowser.cryptoRandomBuffer
+
+exports.performance = perf
+exports.cryptoRandomBuffer = cryptoRandomBuffer