This commit addresses a race condition when showing the message drawer
and opening the settings page from the Message preferences page.
In that situation, the message/edit.php page calls the
message_drawer_helper.showSettings function, which publishes a request
to show the drawer.
In some conditions (notably faster machines, or after MDL-66107) this
event is fired before the message_drawer.init has listened to it.
The solution here is to delay firing of the event until the drawer
announces itself as ready.
This ensures that the event is subscribed to before it is fired.
Unfortunately the babel minify-mangle plugin seems to be abandoned and
in certain circumstances can be very buggy. The only safe options are to
disable it, or to switch to a different minification library.
Not minifying our javascript is not ideal, so this commit updates the
javascript tasks to use a rollup, combined with babel, and terser.
Babel still converts code from ES/UMD/AMD to AMD modules with the
relevant browser support, whilst terser minifies the code.
The rollup bundler handles tracking and creation of sourcemaps, and
supports better parallelisation of the tasks.
Since the upgrade to Node LTS/Gallium requires an upgrade to @babel/core
and eslint, which change the built files anyway, this seems like the
ideal time to make this change.
* Fix navigation from view_contact to view_conversation on an action
such as blocking
* Fix default open message section on overview page depending on which
section has conversations
* Fix message/index.php for users who haven't yet started a
conversation
