update rollup to 0.34.8, to avoid parsing slowdown (#9509)

package.json

@@ -45,7 +45,7 @@
     "argparse": "^1.0.3",
     "chokidar-cli": "1.2.0",
     "jscs": "^1.13.1",
-    "rollup": "^0.33.1",
+    "rollup": "^0.34.8",
     "uglify-js": "^2.6.0"
   }
 }