dart2js cleanup: remove unused imports and variables

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

 // Copyright (c) 2015, 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 cps_ir.optimization.inline;
 
+import 'package:js_ast/js_ast.dart' as js;
+
+import '../dart_types.dart' show DartType, GenericType;
+import '../elements/elements.dart';
+import '../js_backend/codegen/task.dart' show CpsFunctionCompiler;
+import '../js_backend/js_backend.dart' show JavaScriptBackend;
+import '../types/types.dart' show TypeMask;
+import '../universe/call_structure.dart' show CallStructure;
+import '../universe/selector.dart' show Selector;
+import '../world.dart' show World;
 import 'cps_fragment.dart';
 import 'cps_ir_builder.dart' show ThisParameterLocal;
 import 'cps_ir_nodes.dart';
 import 'optimizers.dart';
 import 'type_mask_system.dart' show TypeMaskSystem;
-import '../dart_types.dart' show DartType, GenericType;
-import '../world.dart' show World;
-import '../elements/elements.dart';
-import '../js_backend/js_backend.dart' show JavaScriptBackend;
-import '../js_backend/codegen/task.dart' show CpsFunctionCompiler;
-import '../types/types.dart'
-    show FlatTypeMask, ForwardingTypeMask, TypeMask, UnionTypeMask;
-import '../universe/call_structure.dart' show CallStructure;
-import '../universe/selector.dart' show Selector;
-import 'package:js_ast/js_ast.dart' as js;
 
 /// Inlining stack entries.
 ///
 /// During inlining, a stack is used to detect cycles in the call graph.
 class StackEntry {
   // Dynamically resolved calls might be targeting an adapter function that
   // fills in optional arguments not passed at the call site.  Therefore these
   // calls are represented by the eventual target and the call structure at
   // the call site, which together identify the target.  Statically resolved
   // calls are represented by the target element and a null call structure.
@@ skipping 572 matching lines @@
         (enclosingClass == backend.helpers.jsNumberClass ||
             enclosingClass == backend.helpers.jsDoubleClass ||
             enclosingClass == backend.helpers.jsIntClass)) {
       // These should be handled by operator specialization.
       return true;
     }
     if (target == backend.helpers.stringInterpolationHelper) return true;
     return false;
   }
 }