Remove support for interface in dart2js.

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

Index: sdk/lib/_internal/compiler/implementation/compile_time_constants.dart
diff --git a/sdk/lib/_internal/compiler/implementation/compile_time_constants.dart b/sdk/lib/_internal/compiler/implementation/compile_time_constants.dart
index cb39371caba9a09fc6722648de16404c3eed6f73..dc99d27854c59c90d7ef520afa89aaf0702c759c 100644
--- a/sdk/lib/_internal/compiler/implementation/compile_time_constants.dart
+++ b/sdk/lib/_internal/compiler/implementation/compile_time_constants.dart
@@ -647,11 +647,6 @@ class CompileTimeConstantEvaluator extends Visitor {
     FunctionElement constructor = elements[send];
     constructor = constructor.redirectionTarget;
     ClassElement classElement = constructor.getEnclosingClass();
-    if (classElement.isInterface()) {
-      compiler.resolver.resolveMethodElement(constructor);
-      constructor = constructor.defaultImplementation;
-      classElement = constructor.getEnclosingClass();
-    }
     // The constructor must be an implementation to ensure that field
     // initializers are handled correctly.
     constructor = constructor.implementation;