Add unique identifier to router instance (#9015)
Add unique identifier to router instance (#9015)

* Update to use a historyId to track invalid popstates

* Remove log from debugging

* Use Math.random instead of Date.getTime to avoid mocks

azukaru/next.js,JeromeFitz/next.js,azukaru/next.js,flybayer/next.js,flybayer/next.js,flybayer/next.js,zeit/next.js,zeit/next.js,flybayer/next.js,JeromeFitz/next.js,JeromeFitz/next.js,JeromeFitz/next.js,azukaru/next.js,azukaru/next.js,zeit/next.js