Eliminate constructor return types from summaries.

pkg/analyzer/tool/summary/idl.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.
 
 /**
  * This file is an "idl" style description of the summary format.  It is not
  * executed directly; instead it is parsed and transformed into code that
  * implements the summary format.
  *
  * The code generation process introduces the following non-typical semantics:
@@ skipping 308 matching lines @@
   String name;
 
   /**
    * Type parameters of the executable, if any.  Empty if support for generic
    * method syntax is disabled.
    */
   List<UnlinkedTypeParam> typeParameters;
 
   /**
    * Declared return type of the executable.  Absent if the return type is
-   * `void`.  Note that when strong mode is enabled, the actual return type may
-   * be different due to type inference.
+   * `void` or the executable is a constructor.  Note that when strong mode is
+   * enabled, the actual return type may be different due to type inference.
    */
   UnlinkedTypeRef returnType;
 
   /**
    * Parameters of the executable, if any.  Note that getters have no
    * parameters (hence this will be the empty list), and setters have a single
    * parameter.
    */
   List<UnlinkedParam> parameters;
 
@@ skipping 437 matching lines @@
   /**
    * Indicates whether the variable is declared using the `const` keyword.
    */
   bool isConst;
 
   /**
    * Indicates whether this variable lacks an explicit type declaration.
    */
   bool hasImplicitType;
 }