Hi,
I inspect the react code and in call stacks, found `process.env.NODE_ENV`
is undefined due to which 'SyntheticEvent.call' is not callable.
So, to fix this, i add 'definePlugin' to plugins for `dev` environment in
`webpack.config.js`. Initially it was added only for `production`
environment. but it is needed for both, because React code is conditional
based on environment variables set.
Please find attached patch and review.
Thanks,
Surinder