As i walk through the source, i've tried to trace the webpack running stack.
Then, i find the missing constructors result in uncleasr stack and create a patch
for them.
... when it's not allowed.
I. e. with HMR enabled [chunkhash] for the entry chunk
is not allowed. Now it throws an error.
Also fixes a bug where [chunkhash] doesn't have to correct
length. fixes#1192