Remove support for interface in dart2js.

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

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart2js;
 
 class MessageKind {
   final String template;
   const MessageKind(this.template);
 
@@ skipping 30 matching lines @@
       'missing return');
   static const MAYBE_MISSING_RETURN = const MessageKind(
       'not all paths lead to a return or throw statement');
 
   static const CANNOT_RESOLVE = const MessageKind(
       'cannot resolve #{name}');
   static const CANNOT_RESOLVE_CONSTRUCTOR = const MessageKind(
       'cannot resolve constructor #{constructorName}');
   static const CANNOT_RESOLVE_CONSTRUCTOR_FOR_IMPLICIT = const MessageKind(
       'cannot resolve constructor #{constructorName} for implicit super call');
+  static const INVALID_UNNAMED_CONSTRUCTOR_NAME = const MessageKind(
+      'Error: Unnamed constructor name must be #{name}.');
+  static const INVALID_CONSTRUCTOR_NAME = const MessageKind(
+      'Error: Constructor name must start with #{name}.');
   static const CANNOT_RESOLVE_TYPE = const MessageKind(
       'cannot resolve type #{typeName}');
   static const DUPLICATE_DEFINITION = const MessageKind(
       'duplicate definition of #{name}');
   static const DUPLICATE_IMPORT = const MessageKind(
       'duplicate import of #{name}');
   static const DUPLICATE_EXPORT = const MessageKind(
       'duplicate export of #{name}');
   static const NOT_A_TYPE = const MessageKind(
       '#{node} is not a type');
   static const NOT_A_PREFIX = const MessageKind(
       '#{node} is not a prefix');
   static const NO_SUPER_IN_OBJECT = const MessageKind(
       "'Object' does not have a superclass");
   static const CANNOT_FIND_CONSTRUCTOR = const MessageKind(
       'cannot find constructor #{constructorName}');
-  static const CANNOT_FIND_CONSTRUCTOR2 = const MessageKind(
-      'cannot find constructor #{constructorName} in #{className}');
   static const CYCLIC_CLASS_HIERARCHY = const MessageKind(
       '#{className} creates a cycle in the class hierarchy');
   static const INVALID_RECEIVER_IN_INITIALIZER = const MessageKind(
       'field initializer expected');
   static const NO_SUPER_IN_STATIC = const MessageKind(
       "'super' is only available in instance methods");
   static const DUPLICATE_INITIALIZER = const MessageKind(
       'field #{fieldName} is initialized more than once');
   static const ALREADY_INITIALIZED = const MessageKind(
       '#{fieldName} was already initialized here');
@@ skipping 92 matching lines @@
       'cycle in the compile-time constant computation');
   static const CONSTRUCTOR_IS_NOT_CONST = const MessageKind(
       'constructor is not a const constructor');
 
   static const KEY_NOT_A_STRING_LITERAL = const MessageKind(
       'map-literal key not a string literal');
 
   static const NO_SUCH_LIBRARY_MEMBER = const MessageKind(
       '#{libraryName} has no member named #{memberName}');
 
-  static const CANNOT_INSTANTIATE_INTERFACE = const MessageKind(
-      "cannot instantiate interface '#{interfaceName}'");
-
   static const CANNOT_INSTANTIATE_TYPEDEF = const MessageKind(
       "cannot instantiate typedef '#{typedefName}'");
 
   static const CANNOT_INSTANTIATE_TYPE_VARIABLE = const MessageKind(
       "cannot instantiate type variable '#{typeVariableName}'");
 
   static const NO_DEFAULT_CLASS = const MessageKind(
       "no default class on enclosing interface '#{interfaceName}'");
 
   static const CYCLIC_TYPE_VARIABLE = const MessageKind(
@@ skipping 401 matching lines @@
 
 class CompileTimeConstantError extends Diagnostic {
   CompileTimeConstantError(MessageKind kind, [Map arguments = const {}])
     : super(kind, arguments);
 }
 
 class CompilationError extends Diagnostic {
   CompilationError(MessageKind kind, [Map arguments = const {}])
     : super(kind, arguments);
 }