Handle missing imports/exports/parts.

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;
 
 /**
  * The messages in this file should meet the following guide lines:
  *
  * 1. The message should start with exactly one of "Error", "Internal error",
@@ skipping 597 matching lines @@
 
   static const MessageKind IMPORTED_HERE = const MessageKind(
       'Info: "#{element}" is imported here.');
 
   static const MessageKind OVERRIDE_EQUALS_NOT_HASH_CODE = const MessageKind(
       'Hint: The class "#{class}" overrides "operator==", '
       'but not "get hashCode".');
 
   static const MessageKind PACKAGE_ROOT_NOT_SET = const MessageKind(
       'Error: Cannot resolve "#{uri}". Package root has not been set.');
+  
+  static const MessageKind INTERNAL_LIBRARY_FROM = const MessageKind(
+      'Error: Internal library "#{resolvedUri}" is not accessible from '
+      '"#{importingUri}".');
+  
+  static const MessageKind INTERNAL_LIBRARY = const MessageKind(
+      'Error: Internal library "#{resolvedUri}" is not accessible.');
+  
+  static const MessageKind LIBRARY_NOT_FOUND = const MessageKind(
+      'Error: Library not found "#{resolvedUri}".');
 
   static const MessageKind COMPILER_CRASHED = const MessageKind(
       'Error: The compiler crashed when compiling this element.');
 
   static const MessageKind PLEASE_REPORT_THE_CRASH = const MessageKind('''
 The compiler is broken.
 
 When compiling the above element, the compiler crashed. It is not
 possible to tell if this is caused by a problem in your program or
 not. Regardless, the compiler should not crash.
@@ skipping 184 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);
 }