Split the notifications into 'alert' and 'message' badget with two
different flyouts. Also clean up styling and module behavior.
** Depends on ooui change Id4bbe14ba0bf6c for footers in popups.
** Depends on ooui change Ie93e4d6ed5637c for fixing a bug in
inverted icons.
** MobileFrontend must also be updated to support the new modules
in this patch I168f485d6e54cb4067
In this change:
* Split notifcations into alert and messages and display those in
two different badges.
* Create two separate flyout/popups for each category with their
notifications.
* Create a view-model to control notification state and emit events
for both the popup and the badge to intercept and react to.
* Clean up module load and distribution:
* Create an ext.echo.ui module for javascript-ui support and ooui
widgets.
* Create an ext.echo.nojs module that unifies all base classes that
are needed for both nojs and js support, that the js version
builds upon.
* Create a separate ext.echo.logger module as a singleton that can
be called to perform all logging.
* Clean up style uses
* Move the special page LESS file into nojs module so all styles
load properly even in nojs mode.
* Transfer some of the styling from JS to LESS for consistency.
* Make the 'read more' button load already with the styles it
needs to look like a button, since its behavior is similar in
nojs and js vesions, but before its classes were applied only
by the js, making it inconsistent and also making its appearance
'jump' from a link to a button.
* Delete and clean up all old and unused files.
* Moved 'Help.png' icon from modules/overlay to modules/icons for
later use.
Bug: T108190
Change-Id: I55f440ed9f64c46817f620328a6bb522d44c9ca9