Early in Review Board 7.1's development, a Quick Access feature for

actions was created in order to give people control over actions they

wanted in their hot bar. This was implemented as special, duplicated

actions that used a mixin to indicate they should appear in the hot bar,

and settings that managed the list of configured actions.
That work set the stage for much of the new action infrastructure,

separating out rendering/placement from core functionality, since we

didn't have any easy way to put the action in both places when that

feature was implemented.
This change tears out much of the custom code for Quick Access actions.

The mixin, custom JS-side attributes, and custom view handling have all

been removed.
Now, actions can simply be placed in the Quick Access attachment point,

which will render them as buttons by default. Any action placed there

will activate the action's behavior.
The Unified Banner builds new menu items for each available action and

simultaneously ties its enabled state to the visibility of the

particular action view, keeping that code all consolidated.
Since we're now reusing core action IDs and not using special subclasses

with their own quickaccess- ID prefixes, we need to migrate legacy

actions over for RBCommons customers. This is done by moving to an

all-new per-user setting, quick_access_action_ids. If set, this is

returned directly. If not set, but the previous quick_access_actions

is set, those actions will be moved over, In time, we can get rid of

this logic entirely.

Unit tests pass.
Tested that all Quick Access actions migrated over.
Tested enabling, disabling, and re-enabling all actions.
Verified the resulting settings were correct.