Rename current, origin, scale, origin_scale

This patch renames that fields to have consistent names.
diff --git a/src/compositor-x11.c b/src/compositor-x11.c
index e04ea06..1dd5037 100644
--- a/src/compositor-x11.c
+++ b/src/compositor-x11.c
@@ -420,10 +420,10 @@
 			break;
 		}
 
-		transformed_rect.x1 *= output_base->scale;
-		transformed_rect.y1 *= output_base->scale;
-		transformed_rect.x2 *= output_base->scale;
-		transformed_rect.y2 *= output_base->scale;
+		transformed_rect.x1 *= output_base->current_scale;
+		transformed_rect.y1 *= output_base->current_scale;
+		transformed_rect.x2 *= output_base->current_scale;
+		transformed_rect.y2 *= output_base->current_scale;
 
 		output_rects[i].x = transformed_rect.x1;
 		output_rects[i].y = transformed_rect.y1;
@@ -891,8 +891,8 @@
 	output->base.set_backlight = NULL;
 	output->base.set_dpms = NULL;
 	output->base.switch_mode = NULL;
-	output->base.current = &output->mode;
-	output->base.origin = output->base.current;
+	output->base.current_mode = &output->mode;
+	output->base.original_mode = output->base.current_mode;
 	output->base.make = "xwayland";
 	output->base.model = "none";
 	weston_output_init(&output->base, &c->base,