This adds back `wlr_output::needs_swap`. This allows a backend to request buffer swaps even if the output isn't damaged. This is needed by the DRM backend to trigger pageflips when the cursor moves.  | 
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| .. | ||
| wlr_input_device.h | ||
| wlr_keyboard.h | ||
| wlr_output.h | ||
| wlr_pointer.h | ||
| wlr_tablet_pad.h | ||
| wlr_tablet_tool.h | ||
| wlr_touch.h | ||