Attach type info to extension method and object method tear-offs

test/browser/runtime_tests.js

Index: test/browser/runtime_tests.js
diff --git a/test/browser/runtime_tests.js b/test/browser/runtime_tests.js
index 63f9e67ff24adc9e3ed908c70375583b444d206b..e6fcff766cb275658fdd4da6463aa795b1c92375 100644
--- a/test/browser/runtime_tests.js
+++ b/test/browser/runtime_tests.js
@@ -675,6 +675,16 @@ suite('instanceOf', () => {
     checkType(c.ListBase.listToString,
               dart.functionType(core.String, [core.String]), false, true);
 
+    // Tear-off of extension methods on primitives
+    checkType(dart.bind(3.0, dartx.floor),
+              dart.functionType(core.int, []));
+    checkType(dart.bind(3.0, dartx.floor),
+              dart.functionType(core.String, []), false, true);
+    checkType(dart.bind("", dartx.endsWith),
+              dart.functionType(core.bool, [core.String]));
+    checkType(dart.bind("", dartx.endsWith),
+              dart.functionType(core.bool, [core.int]), false, true);
+
     // Tear off a mixin method
     class Base {
       m(x) {return x;}