[Scale] Refactoring (2): Remove drag-and-drop relics.
[Scale] Refactoring (3): Remove workspace-changed logic.
[Scale] Refactoring (4): _alwaysUpdateZoom removed.
[Scale] Refactoring (5): Get rid of unused workspace controls.
[Scale] Refactoring (6): Move ownership of _workspaces to the view.
[Scale] Refactoring (7): Move more members from display to view.
[Scale] Refactoring (8): Move even more members from display to view.
[Scale] Refactoring (9): Remove clip* members.
[Scale] Refactoring (10): Remove a duplicate handler.
[Scale] Use all available screen space.
[Scale] Refactoring (11): Get rid of WorkspacesView.WorkspacesDisplay.
[Scale] Refactoring (12): Avoid mutual import.
[Scale] Refactoring (13): Remove more drag-and-drop left-overs.
[main.js] Keep internal workspace count in sync with reality.
[main.js] Add a function to move a window to a new workspace.
[Scale] Handle changes in workspace count dynamically.
[Scale] Add a menu option to move a window to a new workspace.
[Scale] Remove some more left-overs.
[Scale] Give the window context menu an ID: 'scale-window-context-menu', for easier theming.
Deprecate Overview.setMessage