Merge pull request electron#229 from electron/user-selected-entitlement

Enable user-selected entitlement for open/save demo

Author: kevinsawicki

assets/mac/parent.plist

@@ -6,5 +6,7 @@
     <true/>
     <key>com.apple.security.application-groups</key>
     <string>VEKTX9H2N7.com.github.electron-api-demos</string>
+    <key>com.apple.security.files.user-selected.read-write</key>
+    <true/>
   </dict>
 </plist>