Revert "Remove 'Element.docRange'."

pkg/analyzer/lib/src/summary/format.dart

Index: pkg/analyzer/lib/src/summary/format.dart
diff --git a/pkg/analyzer/lib/src/summary/format.dart b/pkg/analyzer/lib/src/summary/format.dart
index 641287e85e68b90e4f18592854662127010f11a3..626f4431234a2f108dd3e8aec202d43c8582f3b1 100644
--- a/pkg/analyzer/lib/src/summary/format.dart
+++ b/pkg/analyzer/lib/src/summary/format.dart
@@ -4795,13 +4795,32 @@ abstract class _UnlinkedConstructorInitializerMixin implements idl.UnlinkedConst
 }
 
 class UnlinkedDocumentationCommentBuilder extends Object with _UnlinkedDocumentationCommentMixin implements idl.UnlinkedDocumentationComment {
+  int _length;
+  int _offset;
   String _text;
 
   @override
-  int get length => throw new UnimplementedError('attempt to access deprecated field');
+  int get length => _length ??= 0;
+
+  /**
+   * Length of the documentation comment (prior to replacing '\r\n' with '\n').
+   */
+  void set length(int _value) {
+    assert(_value == null || _value >= 0);
+    _length = _value;
+  }
 
   @override
-  int get offset => throw new UnimplementedError('attempt to access deprecated field');
+  int get offset => _offset ??= 0;
+
+  /**
+   * Offset of the beginning of the documentation comment relative to the
+   * beginning of the file.
+   */
+  void set offset(int _value) {
+    assert(_value == null || _value >= 0);
+    _offset = _value;
+  }
 
   @override
   String get text => _text ??= '';
@@ -4816,8 +4835,10 @@ class UnlinkedDocumentationCommentBuilder extends Object with _UnlinkedDocumenta
     _text = _value;
   }
 
-  UnlinkedDocumentationCommentBuilder({String text})
-    : _text = text;
+  UnlinkedDocumentationCommentBuilder({int length, int offset, String text})
+    : _length = length,
+      _offset = offset,
+      _text = text;
 
   /**
    * Flush [informative] data recursively.
@@ -4829,7 +4850,9 @@ class UnlinkedDocumentationCommentBuilder extends Object with _UnlinkedDocumenta
    * Accumulate non-[informative] data into [signature].
    */
   void collectApiSignature(api_sig.ApiSignature signature) {
+    signature.addInt(this._length ?? 0);
     signature.addString(this._text ?? '');
+    signature.addInt(this._offset ?? 0);
   }
 
   fb.Offset finish(fb.Builder fbBuilder) {
@@ -4838,6 +4861,12 @@ class UnlinkedDocumentationCommentBuilder extends Object with _UnlinkedDocumenta
       offset_text = fbBuilder.writeString(_text);
     }
     fbBuilder.startTable();
+    if (_length != null && _length != 0) {
+      fbBuilder.addUint32(0, _length);
+    }
+    if (_offset != null && _offset != 0) {
+      fbBuilder.addUint32(2, _offset);
+    }
     if (offset_text != null) {
       fbBuilder.addOffset(1, offset_text);
     }
@@ -4858,13 +4887,21 @@ class _UnlinkedDocumentationCommentImpl extends Object with _UnlinkedDocumentati
 
   _UnlinkedDocumentationCommentImpl(this._bc, this._bcOffset);
 
+  int _length;
+  int _offset;
   String _text;
 
   @override
-  int get length => throw new UnimplementedError('attempt to access deprecated field');
+  int get length {
+    _length ??= const fb.Uint32Reader().vTableGet(_bc, _bcOffset, 0, 0);
+    return _length;
+  }
 
   @override
-  int get offset => throw new UnimplementedError('attempt to access deprecated field');
+  int get offset {
+    _offset ??= const fb.Uint32Reader().vTableGet(_bc, _bcOffset, 2, 0);
+    return _offset;
+  }
 
   @override
   String get text {
@@ -4877,12 +4914,16 @@ abstract class _UnlinkedDocumentationCommentMixin implements idl.UnlinkedDocumen
   @override
   Map<String, Object> toJson() {
     Map<String, Object> _result = <String, Object>{};
+    if (length != 0) _result["length"] = length;
+    if (offset != 0) _result["offset"] = offset;
     if (text != '') _result["text"] = text;
     return _result;
   }
 
   @override
   Map<String, Object> toMap() => {
+    "length": length,
+    "offset": offset,
     "text": text,
   };