Temporarily disable TouchList constructor to implement varargs.

tools/dom/templates/html/impl/impl_TouchList.darttemplate

Index: tools/dom/templates/html/impl/impl_TouchList.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_TouchList.darttemplate b/tools/dom/templates/html/impl/impl_TouchList.darttemplate
index d984852a6bb088cbb0bc3597356cfed7c6efd6f3..06c7b673b8be754b8d5344d6e289f97db452d159 100644
--- a/tools/dom/templates/html/impl/impl_TouchList.darttemplate
+++ b/tools/dom/templates/html/impl/impl_TouchList.darttemplate
@@ -10,6 +10,7 @@ $(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$MIXINS$IMPLEMENTS$NATIV
   /// NB: This constructor likely does not work as you might expect it to! This
   /// constructor will simply fail (returning null) if you are not on a device
   /// with touch enabled. See dartbug.com/8314.
-  factory $CLASSNAME() => document._createTouchList();
+  // TODO(5760): createTouchList now uses varargs.
+  factory $CLASSNAME() => null;//document._createTouchList();
 $!MEMBERS
 }