Remove dart backend

lib/runtime/dart_logging_runtime.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 dev_compiler.runtime.dart_logging_runtime;
-
-import 'dart:mirrors' as mirrors;
-
-import 'dart_runtime.dart' as rt;
-export 'dart_runtime.dart' show Arity, getArity, type;
-
-import 'package:stack_trace/stack_trace.dart';
-
-// Logging / updating CastRecords for cases that alway pass in Dart and DDC
-// is expensive.  They are also less interesting, so filter out by default.
-const bool _skipSuccess = true;
-
-class CastRecord {
-  final Type runtimeType;
-  final Type staticType;
-
-  /// True if the dev_compiler would allow this cast. Otherwise false.
-  final bool soundCast;
-
-  /// True if Dart checked mode would allow this cast. Otherwise false.
-  final bool dartCast;
-
-  CastRecord(this.runtimeType, this.staticType, this.soundCast, this.dartCast);
-}
-
-// Register a handler to process CastRecords.  The default (see below) just
-// prints a summary at the end.
-typedef void CastRecordHandler(String key, CastRecord record);
-CastRecordHandler castRecordHandler = _record;
-
-var _cache = <Type, Map<Type, CastRecord>>{};
-
-Map<Type, CastRecord> _cacheGen() => <Type, CastRecord>{};
-
-void _addToCache(Type runtimeType, Type staticType, CastRecord record) {
-  _cache.putIfAbsent(runtimeType, _cacheGen)[staticType] = record;
-}
-
-CastRecord _lookupInCache(Type runtimeType, Type staticType) {
-  var subcache = _cache[runtimeType];
-  if (subcache == null) return null;
-  return subcache[staticType];
-}
-
-var _successCache = <Type, Set<Type>>{};
-
-dynamic cast(dynamic obj, Type fromType, Type staticType,
-    [String kind, String key, bool dartIs, bool isGround]) {
-  var runtimeType = obj.runtimeType;
-  // Short-circuit uninteresting cases.
-  if (_skipSuccess && _successCache.containsKey(staticType)) {
-    if (_successCache[staticType].contains(runtimeType)) {
-      return obj;
-    }
-  }
-
-  if (key == null) {
-    // If no key is past in, use the caller's frame as a key.
-    final trace = new Trace.current(1);
-    final frame = trace.frames.first;
-    key = frame.toString();
-  }
-
-  CastRecord record = _lookupInCache(runtimeType, staticType);
-  if (record == null) {
-    bool soundCast = true;
-    bool dartCast = true;
-    // TODO(vsm): Use instanceOf once we settle on nullability.
-    try {
-      rt.cast(obj, staticType);
-    } catch (e) {
-      soundCast = false;
-    }
-    if (obj == null) {
-      dartCast = true;
-    } else {
-      // TODO(vsm): We could avoid mirror code by requiring the caller to pass
-      // in obj is TypeLiteral as a parameter.  We can't do that once we have a
-      // Type object instead.
-      final staticMirror = mirrors.reflectType(staticType);
-      final instanceMirror = mirrors.reflect(obj);
-      final classMirror = instanceMirror.type;
-      dartCast = classMirror.isSubtypeOf(staticMirror);
-    }
-    if (_skipSuccess && dartCast && soundCast) {
-      _successCache
-          .putIfAbsent(staticType, () => new Set<Type>())
-          .add(runtimeType);
-      return obj;
-    }
-    record = new CastRecord(runtimeType, staticType, soundCast, dartCast);
-    _addToCache(runtimeType, staticType, record);
-  }
-  castRecordHandler(key, record);
-  return obj;
-}
-
-dynamic wrap(Function build(Function _), Function f, Type fromType, Type toType,
-    String kind, String key, bool dartIs) {
-  if (f == null) return null;
-  return build(f);
-}
-
-// The default handler simply records all CastRecords and prints a summary
-// at the end.
-final _recordMap = new Map<String, List<CastRecord>>();
-void _record(String key, CastRecord record) {
-  _recordMap.putIfAbsent(key, () => <CastRecord>[]).add(record);
-}
-
-String summary({bool clear: true}) {
-  final buffer = new StringBuffer();
-  _recordMap.forEach((String key, List<CastRecord> records) {
-    int success = 0;
-    int mismatch = 0;
-    int error = 0;
-    int failure = 0;
-    Type staticType = null;
-    var runtimeTypes = new Set<Type>();
-    for (var record in records) {
-      if (staticType == null) {
-        staticType = record.staticType;
-      } else {
-        // Are these canonicalized?
-        // assert(staticType == record.staticType);
-      }
-      runtimeTypes.add(record.runtimeType);
-      if (record.soundCast) {
-        if (record.dartCast) {
-          success++;
-        } else {
-          error++;
-        }
-      } else {
-        if (record.dartCast) {
-          mismatch++;
-        } else {
-          failure++;
-        }
-      }
-    }
-    final total = success + mismatch + error + failure;
-    assert(total != 0);
-    if (success < total) {
-      buffer.writeln('Key $key:');
-      buffer.writeln(' - static type: $staticType');
-      buffer.writeln(' - runtime types: $runtimeTypes');
-      final category = (String cat, int val) =>
-          buffer.writeln(' - $cat: $val (${val / total})');
-      category('success', success);
-      category('failure', failure);
-      category('mismatch', mismatch);
-      category('error', error);
-    }
-  });
-  if (clear) {
-    _recordMap.clear();
-  }
-  return buffer.toString();
-}