webpack/weblabels-plugin: Fix Web Labels table in production mode
Recent changes in webpack modified the content of the JSON stats object when compiling assets in production mode. Notably a module chunk is now identified by an integer instead of its name.
So add an extra mapping between a chunk id and its name in order to fix the generated Web Labels table.
This plugin definitely needs to have some tests.
@vlorentz started this work in !75 (closed) but I will create a task to not forget about it.
Migrated from D5241 (view on Phabricator)