Use common.dart to re-export commonly used entities.

pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart

 // Copyright (c) 2013, 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.
 
 library dart2js.ir_builder;
 
+import '../closure.dart' hide ClosureScope;
+import '../common.dart';
 import '../common/names.dart' show
     Names,
     Selectors;
 import '../compile_time_constants.dart' show
     BackendConstantEnvironment;
 import '../constants/constant_system.dart';
 import '../constants/values.dart' show
     ConstantValue,
     PrimitiveConstantValue;
 import '../dart_types.dart';
-import '../diagnostics/invariant.dart' show
-    invariant;
 import '../elements/elements.dart';
 import '../io/source_information.dart';
+import '../js/js.dart' as js show
+    js,
+    LiteralStatement,
+    Template;
+import '../native/native.dart' show
+    NativeBehavior;
 import '../tree/tree.dart' as ast;
 import '../types/types.dart' show
     TypeMask;
-import '../closure.dart' hide ClosureScope;
 import '../universe/call_structure.dart' show
     CallStructure;
 import '../universe/selector.dart' show
     Selector,
     SelectorKind;
-import 'cps_ir_nodes.dart' as ir;
+
 import 'cps_ir_builder_task.dart' show
     DartCapturedVariables,
     GlobalProgramInformation;
+import 'cps_ir_nodes.dart' as ir;
 
-import '../common.dart' as types show
-    TypeMask;
-import '../js/js.dart' as js show Template, js, LiteralStatement;
-import '../native/native.dart' show
-    NativeBehavior;
 
 /// A mapping from variable elements to their compile-time values.
 ///
 /// Map elements denoted by parameters and local variables to the
 /// [ir.Primitive] that is their value.  Parameters and locals are
 /// assigned indexes which can be used to refer to them.
 class Environment {
   /// A map from locals to their environment index.
   final Map<Local, int> variable2index;
 
@@ skipping 2639 matching lines @@
   ir.Primitive buildInvocationMirror(Selector selector,
                                      List<ir.Primitive> arguments) {
     return addPrimitive(new ir.CreateInvocationMirror(selector, arguments));
   }
 
   ir.Primitive buildForeignCode(js.Template codeTemplate,
                                 List<ir.Primitive> arguments,
                                 NativeBehavior behavior,
                                 {Element dependency}) {
     assert(behavior != null);
-    types.TypeMask type = program.getTypeMaskForForeign(behavior);
+    TypeMask type = program.getTypeMaskForForeign(behavior);
     ir.Primitive result = _continueWithExpression((k) => new ir.ForeignCode(
         codeTemplate,
         type,
         arguments,
         behavior,
         k,
         dependency: dependency));
     if (!codeTemplate.isExpression) {
       // Close the term if this is a "throw" expression or native body.
       add(new ir.Unreachable());
@@ skipping 175 matching lines @@
 }
 
 class SwitchCaseInfo {
   final List<ir.Primitive> constants = <ir.Primitive>[];
   final SubbuildFunction buildBody;
 
   SwitchCaseInfo(this.buildBody);
 
   void addConstant(ir.Primitive constant) => constants.add(constant);
 }