fix attributes with mustache tag as final chunk

compiler/parse/state/tag.js

@@ -203,10 +203,8 @@ function readQuotedAttributeValue ( parser, quoteMark ) {
 			else if ( parser.match( quoteMark ) ) {
 				currentChunk.end = parser.index++;
 
-				if ( currentChunk.data ) {
+				if ( currentChunk.data ) chunks.push( currentChunk );
-					chunks.push( currentChunk );
+				return chunks;
-					return chunks;
-				}
 			}
 
 			else {

test/parser/attribute-dynamic-boolean/input.svelte

@@ -0,0 +1 @@
+<textarea readonly='{{readonly}}'></textarea>

test/parser/attribute-dynamic-boolean/output.json

@@ -0,0 +1,39 @@
+{
+	"html": {
+		"start": 0,
+		"end": 45,
+		"type": "Fragment",
+		"children": [
+			{
+				"start": 0,
+				"end": 45,
+				"type": "Element",
+				"name": "textarea",
+				"attributes": [
+					{
+						"start": 10,
+						"end": 33,
+						"type": "Attribute",
+						"name": "readonly",
+						"value": [
+							{
+								"start": 20,
+								"end": 32,
+								"type": "MustacheTag",
+								"expression": {
+									"start": 22,
+									"end": 30,
+									"type": "Identifier",
+									"name": "readonly"
+								}
+							}
+						]
+					}
+				],
+				"children": []
+			}
+		]
+	},
+	"css": null,
+	"js": null
+}