Permissions: use newly supported required attribute on Dictionary properties.

Source/modules/permissions/PermissionDescriptor.idl

Index: Source/modules/permissions/PermissionDescriptor.idl
diff --git a/Source/modules/permissions/PermissionDescriptor.idl b/Source/modules/permissions/PermissionDescriptor.idl
index 551a767b1472fbd6a9d59741fe3fcbc69cfe92a2..22e17256512a02321c377136a32837d2aed5ae79 100644
--- a/Source/modules/permissions/PermissionDescriptor.idl
+++ b/Source/modules/permissions/PermissionDescriptor.idl
@@ -13,5 +13,5 @@ enum PermissionName {
 // permissions will extend it. The methods reading it will re-parse it depending
 // on the name.
 dictionary PermissionDescriptor {
-    /* required */ PermissionName name;
+    required PermissionName name;
 };