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

pkg/compiler/lib/src/code_buffer.dart

-// Copyright (c) 2012, 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.
-
-part of dart2js;
-
-class CodeBuffer implements StringBuffer {
-
-  StringBuffer buffer = new StringBuffer();
-  List<CodeBufferMarker> markers = new List<CodeBufferMarker>();
-
-  int lastBufferOffset = 0;
-  int mappedRangeCounter = 0;
-
-  CodeBuffer();
-
-  int get length => buffer.length;
-  bool get isEmpty => buffer.isEmpty;
-  bool get isNotEmpty => buffer.isNotEmpty;
-
-  CodeBuffer add(var object) {
-    write(object);
-    return this;
-  }
-  /**
-   * Converts [object] to a string and adds it to the buffer. If [object] is a
-   * [CodeBuffer], adds its markers to [markers].
-   */
-  CodeBuffer write(var object) {
-    if (object is CodeBuffer) {
-      return addBuffer(object);
-    }
-    if (mappedRangeCounter == 0) setSourceLocation(null);
-    buffer.write(object);
-    return this;
-  }
-
-  CodeBuffer writeAll(Iterable<Object> objects, [String separator = ""]) {
-    Iterator iterator = objects.iterator;
-    if (!iterator.moveNext()) return this;
-    if (separator.isEmpty) {
-      do {
-        write(iterator.current);
-      } while (iterator.moveNext());
-    } else {
-      write(iterator.current);
-      while (iterator.moveNext()) {
-        write(separator);
-        write(iterator.current);
-      }
-    }
-    return this;
-  }
-
-  CodeBuffer writeln([var object = ""]) {
-    return write(object).write("\n");
-  }
-
-  CodeBuffer addBuffer(CodeBuffer other) {
-    if (other.markers.length > 0) {
-      CodeBufferMarker firstMarker = other.markers[0];
-      int offsetDelta =
-          buffer.length + firstMarker.offsetDelta - lastBufferOffset;
-      markers.add(new CodeBufferMarker(offsetDelta,
-                                       firstMarker.sourcePosition));
-      for (int i = 1; i < other.markers.length; ++i) {
-        markers.add(other.markers[i]);
-      }
-      lastBufferOffset = buffer.length + other.lastBufferOffset;
-    }
-    buffer.write(other.getText());
-    return this;
-  }
-
-  CodeBuffer addAll(Iterable<Object> iterable) => writeAll(iterable);
-
-  CodeBuffer writeCharCode(int charCode) {
-    buffer.writeCharCode(charCode);
-    return this;
-  }
-
-  CodeBuffer clear() {
-    buffer = new StringBuffer();
-    markers.clear();
-    lastBufferOffset = 0;
-    return this;
-  }
-
-  String toString() {
-    throw "Don't use CodeBuffer.toString() since it drops sourcemap data.";
-  }
-
-  String getText() {
-    return buffer.toString();
-  }
-
-  void beginMappedRange() {
-    ++mappedRangeCounter;
-  }
-
-  void endMappedRange() {
-    assert(mappedRangeCounter > 0);
-    --mappedRangeCounter;
-  }
-
-  void setSourceLocation(var sourcePosition) {
-    if (sourcePosition == null) {
-      if (markers.length > 0 && markers.last.sourcePosition == null) return;
-    }
-    int offsetDelta = buffer.length - lastBufferOffset;
-    markers.add(new CodeBufferMarker(offsetDelta, sourcePosition));
-    lastBufferOffset = buffer.length;
-  }
-
-  void forEachSourceLocation(void f(int targetOffset, var sourcePosition)) {
-    int targetOffset = 0;
-    markers.forEach((marker) {
-      targetOffset += marker.offsetDelta;
-      f(targetOffset, marker.sourcePosition);
-    });
-  }
-}
-
-class CodeBufferMarker {
-  final int offsetDelta;
-  final sourcePosition;
-
-  CodeBufferMarker(this.offsetDelta, this.sourcePosition);
-}