simplify some slot_name stuff

src/compile/nodes/Slot.ts

@@ -5,6 +5,7 @@ import Attribute from './Attribute';
 export default class Slot extends Element {
 	type: 'Element';
 	name: string;
+	slot_name: string;
 	attributes: Attribute[];
 	children: Node[];
 
@@ -27,8 +28,8 @@ export default class Slot extends Element {
 					});
 				}
 
-				const slot_name = attr.value[0].data;
-				if (slot_name === 'default') {
+				this.slot_name = attr.value[0].data;
+				if (this.slot_name === 'default') {
 					component.error(attr, {
 						code: `invalid-slot-name`,
 						message: `default is a reserved word — it cannot be used as a slot name`
@@ -46,6 +47,8 @@ export default class Slot extends Element {
 			// validator.slots.add(slot_name);
 		});
 
+		if (!this.slot_name) this.slot_name = 'default';
+
 		// if (node.attributes.length === 0) && validator.slots.has('default')) {
 		// 	validator.error(node, {
 		// 		code: `duplicate-slot`,

src/compile/render-dom/wrappers/Element/index.ts

@@ -20,6 +20,7 @@ import add_event_handlers from '../shared/add_event_handlers';
 import add_actions from '../shared/add_actions';
 import create_debugging_comment from '../shared/create_debugging_comment';
 import { get_context_merger } from '../shared/get_context_merger';
+import Slot from '../../../nodes/Slot';
 
 const events = [
 	{
@@ -213,8 +214,7 @@ export default class ElementWrapper extends Wrapper {
 		const { renderer } = this;
 
 		if (this.node.name === 'slot') {
-			const slot_name = this.node.get_static_attribute_value('name') || 'default';
-			renderer.slots.add(slot_name);
+			renderer.slots.add((this.node as Slot).slot_name);
 		}
 
 		if (this.node.name === 'noscript') return;

src/compile/render-dom/wrappers/Slot.ts

@@ -55,7 +55,7 @@ export default class SlotWrapper extends Wrapper {
 	) {
 		const { renderer } = this;
 
-		const slot_name = this.node.get_static_attribute_value('name') || 'default';
+		const { slot_name } = this.node;
 		renderer.slots.add(slot_name);
 
 		let get_slot_changes;

src/compile/render-ssr/handlers/Slot.ts

@@ -2,10 +2,7 @@ import { quote_prop_if_necessary } from '../../../utils/names';
 import get_slot_data from '../../utils/get_slot_data';
 
 export default function(node, renderer, options) {
-	const name = node.attributes.find(attribute => attribute.name === 'name');
-
-	const slot_name = name && name.chunks[0].data || 'default';
-	const prop = quote_prop_if_necessary(slot_name);
+	const prop = quote_prop_if_necessary(node.slot_name);
 
 	const slot_data = get_slot_data(node.attributes, true);