Runtime support for the new parameter specification.

lib/compiler/implementation/ssa/builder.dart

Index: lib/compiler/implementation/ssa/builder.dart
===================================================================
--- lib/compiler/implementation/ssa/builder.dart	(revision 12238)
+++ lib/compiler/implementation/ssa/builder.dart	(working copy)
@@ -2429,8 +2429,8 @@
           'More than one expression in JS_HAS_EQUALS()', node: node);
     }
     addGenericSendArgumentsToList(node.arguments, inputs);
-    String name = backend.namer.instanceMethodName(
-        currentLibrary, Elements.OPERATOR_EQUALS, 1);
+    String name =
+        backend.namer.instanceMethodNameByArity(Elements.OPERATOR_EQUALS, 1);
     push(new HForeign(new DartString.literal('!!#.$name'),
                       const LiteralDartString('bool'),
                       inputs));