* Remember scroll position on error
* Added comment + check if lastScroll was set
* Remove check for lastAppProps
* Use events to make scroll persistence dev-only
* Return EventEmitter from next()
* Update next-dev.js
* Make sure lastAppProps always have some value.
* Revert "Make sure lastAppProps always have some value."
This reverts commit b4ae722d9c1a4460e17dbdc041b111cbd492b2aa.
* Throw an error, if we found an empty object from getInitialProps.
* Add proper tests for getInitialProps empty check.
