Add the ability to link to members and constructors of other classes in Dartdoc.

utils/dartdoc/files.dart

Index: utils/dartdoc/files.dart
diff --git a/utils/dartdoc/files.dart b/utils/dartdoc/files.dart
index a51c78c33ad8918d31178ca5bde874839c1266c3..d76f1e3361caa26035241ca4f08e8acf8b455c37 100644
--- a/utils/dartdoc/files.dart
+++ b/utils/dartdoc/files.dart
@@ -69,7 +69,12 @@ typeUrl(Type type) {
 }
 
 /** Gets the URL for the documentation for [member]. */
-memberUrl(Member member) => '${typeUrl(member.declaringType)}#${member.name}';
+memberUrl(Member member) {
+  final typeUrl = typeUrl(member.declaringType);
+  if (!member.isConstructor) return '$typeUrl#${member.name}';
+  if (member.constructorName == '') return '$typeUrl#new:${member.name}';
+  return '$typeUrl#new:${member.name}.${member.constructorName}';
+}
 
 /** Gets the anchor id for the document for [member]. */
 memberAnchor(Member member) => '${member.name}';