Revert "Move dart2js from sdk/lib/_internal/compiler to pkg/compiler"

pkg/compiler/lib/src/util/setlet.dart

Index: pkg/compiler/lib/src/util/setlet.dart
diff --git a/pkg/compiler/lib/src/util/setlet.dart b/pkg/compiler/lib/src/util/setlet.dart
deleted file mode 100644
index 10c0224487c73b80b0b6ca0b14cccf7e18323bec..0000000000000000000000000000000000000000
--- a/pkg/compiler/lib/src/util/setlet.dart
+++ /dev/null
@@ -1,312 +0,0 @@
-// 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.util.setlet;
-
-import 'dart:collection' show IterableBase;
-
-class Setlet<E> extends IterableBase<E> implements Set<E> {
-  static const _MARKER = const _SetletMarker();
-  static const CAPACITY = 8;
-
-  // The setlet can be in one of four states:
-  //
-  //   * Empty          (extra: null,   contents: marker)
-  //   * Single element (extra: null,   contents: element)
-  //   * List-backed    (extra: length, contents: list)
-  //   * Set-backed     (extra: marker, contents: set)
-  //
-  // When the setlet is list-backed, the list in the contents field
-  // may have empty slots filled with the marker value.
-  var _contents = _MARKER;
-  var _extra;
-
-  Setlet();
-  Setlet.from(Iterable<E> elements) {
-    addAll(elements);
-  }
-
-  Iterator<E> get iterator {
-    if (_extra == null) {
-      return new _SetletSingleIterator<E>(_contents);
-    } else if (_MARKER == _extra) {
-      return _contents.iterator;
-    } else {
-      return new _SetletListIterator<E>(_contents, _extra);
-    }
-  }
-
-  int get length {
-    if (_extra == null) {
-      return (_MARKER == _contents) ? 0 : 1;
-    } else if (_MARKER == _extra) {
-      return _contents.length;
-    } else {
-      return _extra;
-    }
-  }
-
-  bool get isEmpty {
-    if (_extra == null) {
-      return _MARKER == _contents;
-    } else if (_MARKER == _extra) {
-      return _contents.isEmpty;
-    } else {
-      return _extra == 0;
-    }
-  }
-
-  bool contains(E element) {
-    if (_extra == null) {
-      return _contents == element;
-    } else if (_MARKER == _extra) {
-      return _contents.contains(element);
-    } else {
-      for (int remaining = _extra, i = 0; remaining > 0 && i < CAPACITY; i++) {
-        var candidate = _contents[i];
-        if (_MARKER == candidate) continue;
-        if (candidate == element) return true;
-        remaining--;
-      }
-      return false;
-    }
-  }
-
-  bool add(E element) {
-    if (_extra == null) {
-      if (_MARKER == _contents) {
-        _contents = element;
-        return true;
-      } else if (_contents == element) {
-        // Do nothing.
-        return false;
-      } else {
-        List list = new List(CAPACITY);
-        list[0] = _contents;
-        list[1] = element;
-        _contents = list;
-        _extra = 2;  // Two elements.
-        return true;
-      }
-    } else if (_MARKER == _extra) {
-      return _contents.add(element);
-    } else {
-      int remaining = _extra;
-      int index = 0;
-      int copyTo, copyFrom;
-      while (remaining > 0 && index < CAPACITY) {
-        var candidate = _contents[index++];
-        if (_MARKER == candidate) {
-          // Keep track of the last range of empty slots in the
-          // list. When we're done we'll move all the elements
-          // after those empty slots down, so that adding an element
-          // after that will preserve the insertion order.
-          if (copyFrom == index - 1) {
-            copyFrom++;
-          } else {
-            copyTo = index - 1;
-            copyFrom = index;
-          }
-          continue;
-        } else if (candidate == element) {
-          return false;
-        }
-        remaining--;
-      }
-      if (index < CAPACITY) {
-        _contents[index] = element;
-        _extra++;
-      } else if (_extra < CAPACITY) {
-        // Move the last elements down into the last empty slots
-        // so that we have empty slots after the last element.
-        while (copyFrom < CAPACITY) {
-          _contents[copyTo++] = _contents[copyFrom++];
-        }
-        // Insert the new element as the last element.
-        _contents[copyTo++] = element;
-        _extra++;
-        // Clear all elements after the new last elements to
-        // make sure we don't keep extra stuff alive.
-        while (copyTo < CAPACITY) _contents[copyTo++] = null;
-      } else {
-        _contents = new Set<E>()..addAll(_contents)..add(element);
-        _extra = _MARKER;
-      }
-      return true;
-    }
-  }
-
-  void addAll(Iterable<E> elements) {
-    elements.forEach((each) => add(each));
-  }
-
-  E lookup(Object element) {
-    if (_extra == null) {
-      return _contents == element ? _contents : null;
-    } else if (_MARKER == _extra) {
-      return _contents.lookup(element);
-    } else {
-      for (int remaining = _extra, i = 0; remaining > 0 && i < CAPACITY; i++) {
-        var candidate = _contents[i];
-        if (_MARKER == candidate) continue;
-        if (candidate == element) return candidate;
-        remaining--;
-      }
-      return null;
-    }
-  }
-
-  bool remove(E element) {
-    if (_extra == null) {
-      if (_contents == element) {
-        _contents = _MARKER;
-        return true;
-      } else {
-        return false;
-      }
-    } else if (_MARKER == _extra) {
-      return _contents.remove(element);
-    } else {
-      for (int remaining = _extra, i = 0; remaining > 0 && i < CAPACITY; i++) {
-        var candidate = _contents[i];
-        if (_MARKER == candidate) continue;
-        if (candidate == element) {
-          _contents[i] = _MARKER;
-          _extra--;
-          return true;
-        }
-        remaining--;
-      }
-      return false;
-    }
-  }
-
-  void removeAll(Iterable<Object> other) {
-    other.forEach(remove);
-  }
-
-  void removeWhere(bool test(E element)) {
-    if (_extra == null) {
-      if (test(_contents)) {
-        _contents = _MARKER;
-      }
-    } else if (_MARKER == _extra) {
-      _contents.removeWhere(test);
-    } else {
-      for (int remaining = _extra, i = 0; remaining > 0 && i < CAPACITY; i++) {
-        var candidate = _contents[i];
-        if (_MARKER == candidate) continue;
-        if (test(candidate)) {
-          _contents[i] = _MARKER;
-          _extra--;
-        }
-        remaining--;
-      }
-    }
-  }
-
-  void retainWhere(bool test(E element)) {
-    removeWhere((E element) => !test(element));
-  }
-
-  void retainAll(Iterable<Object> elements) {
-    Set set = elements is Set ? elements : elements.toSet();
-    removeWhere((E element) => !set.contains(element));
-  }
-
-  void forEach(void action(E element)) {
-    if (_extra == null) {
-      if (_MARKER != _contents) action(_contents);
-    } else if (_MARKER == _extra) {
-      _contents.forEach(action);
-    } else {
-      for (int remaining = _extra, i = 0; remaining > 0 && i < CAPACITY; i++) {
-        var element = _contents[i];
-        if (_MARKER == element) continue;
-        action(element);
-        remaining--;
-      }
-    }
-  }
-
-  bool containsAll(Iterable<E> other) {
-    for (E e in other) {
-      if (!this.contains(e)) return false;
-    };
-    return true;
-  }
-
-  clear() {
-    _contents = _MARKER;
-    _extra = null;
-  }
-
-  Set<E> union(Set<E> other) => new Set<E>.from(this)..addAll(other);
-
-  Setlet<E> intersection(Set<E> other) =>
-      new Setlet<E>.from(this.where((e) => other.contains(e)));
-
-  Setlet<E> difference(Set<E> other) =>
-      new Setlet<E>.from(this.where((e) => !other.contains(e)));
-
-  Setlet<E> toSet() {
-    Setlet<E> result = new Setlet<E>();
-    if (_extra == null) {
-      result._contents = _contents;
-    } else if (_extra == _MARKER) {
-      result._extra = _MARKER;
-      result._contents = _contents.toSet();
-    } else {
-      result._extra = _extra;
-      result._contents = _contents.toList();
-    }
-    return result;
-  }
-}
-
-class _SetletMarker {
-  const _SetletMarker();
-  toString() => "-";
-}
-
-class _SetletSingleIterator<E> implements Iterator<E> {
-  var _element;
-  E _current;
-  _SetletSingleIterator(this._element);
-
-  E get current => _current;
-
-  bool moveNext() {
-    if (Setlet._MARKER == _element) {
-      _current = null;
-      return false;
-    }
-    _current = _element;
-    _element = Setlet._MARKER;
-    return true;
-  }
-}
-
-class _SetletListIterator<E> implements Iterator<E> {
-  final List _list;
-  int _remaining;
-  int _index = 0;
-  E _current;
-  _SetletListIterator(this._list, this._remaining);
-
-  E get current => _current;
-
-  bool moveNext() {
-    while (_remaining > 0) {
-      var candidate = _list[_index++];
-      if (Setlet._MARKER != candidate) {
-        _current = candidate;
-        _remaining--;
-        return true;
-      }
-    }
-    _current = null;
-    return false;
-  }
-}