Always explicitely give a type to HInvokeStatic, and make the literal map know it's a map.

sdk/lib/_internal/compiler/implementation/native_handler.dart

Index: sdk/lib/_internal/compiler/implementation/native_handler.dart
===================================================================
--- sdk/lib/_internal/compiler/implementation/native_handler.dart	(revision 18207)
+++ sdk/lib/_internal/compiler/implementation/native_handler.dart	(working copy)
@@ -824,7 +824,7 @@
     // TODO(ngeoffray): For static methods, we could pass a method with a
     // defined arity.
     Element helper = builder.backend.getClosureConverter();
-    builder.pushInvokeHelper2(helper, local, arity);
+    builder.pushInvokeHelper2(helper, local, arity, HType.UNKNOWN);
     HInstruction closure = builder.pop();
     return closure;
   }