Import wpt@bd99724e428dae78082983eab4675480c43f6234

third_party/WebKit/LayoutTests/resources/idlharness.js

Index: third_party/WebKit/LayoutTests/resources/idlharness.js
diff --git a/third_party/WebKit/LayoutTests/resources/idlharness.js b/third_party/WebKit/LayoutTests/resources/idlharness.js
index 6089646591f2d1364c382da64263f7a153668f34..7d0abf4bfc397e31f4bdabe4d85001601a316c1e 100644
--- a/third_party/WebKit/LayoutTests/resources/idlharness.js
+++ b/third_party/WebKit/LayoutTests/resources/idlharness.js
@@ -447,6 +447,14 @@ IdlArray.prototype.assert_type_is = function(value, type)
         return;
     }
 
+    if (type.generic === "Promise") {
+        assert_own_property(value, "then", "Attribute with a Promise type has a then property");
+        // TODO: Ideally, we would check on project fulfillment
+        // that we get the right type
+        // but that would require making the type check async
+        return;
+    }
+
     type = type.idlType;
 
     switch(type)