dart2js cleanup: remove unused imports and variables

pkg/compiler/lib/src/dump_info.dart

Index: pkg/compiler/lib/src/dump_info.dart
diff --git a/pkg/compiler/lib/src/dump_info.dart b/pkg/compiler/lib/src/dump_info.dart
index 726d914b8d04ae9d1e2c74cc95cb70a566e3b5e1..54ca88ff770403ac4d4f8ea682f76d38934439dd 100644
--- a/pkg/compiler/lib/src/dump_info.dart
+++ b/pkg/compiler/lib/src/dump_info.dart
@@ -5,21 +5,21 @@
 library dump_info;
 
 import 'dart:convert'
-    show ChunkedConversionSink, HtmlEscape, JsonEncoder, StringConversionSink;
+    show ChunkedConversionSink, JsonEncoder, StringConversionSink;
 
 import 'package:dart2js_info/info.dart';
 
-import 'common.dart';
 import 'common/tasks.dart' show CompilerTask;
-import 'constants/values.dart' show ConstantValue, InterceptorConstantValue;
+import 'common.dart';
 import 'compiler.dart' show Compiler;
+import 'constants/values.dart' show ConstantValue, InterceptorConstantValue;
 import 'deferred_load.dart' show OutputUnit;
 import 'elements/elements.dart';
 import 'elements/visitor.dart';
 import 'info/send_info.dart' show collectSendMeasurements;
+import 'js/js.dart' as jsAst;
 import 'js_backend/js_backend.dart' show JavaScriptBackend;
 import 'js_emitter/full_emitter/emitter.dart' as full show Emitter;
-import 'js/js.dart' as jsAst;
 import 'types/types.dart' show TypeMask;
 import 'universe/universe.dart' show ReceiverConstraint;
 import 'universe/world_impact.dart'