Reland transformation of async functions.

runtime/vm/ast.h

 // 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.
 
 #ifndef VM_AST_H_
 #define VM_AST_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/growable_array.h"
@@ skipping 147 matching lines @@
   LocalScope* scope() const { return scope_; }
 
   SourceLabel* label() const { return label_; }
   void set_label(SourceLabel* value) { label_ = value; }
 
   void VisitChildren(AstNodeVisitor* visitor) const;
 
   void Add(AstNode* node) { nodes_.Add(node); }
   intptr_t length() const { return nodes_.length(); }
   AstNode* NodeAt(intptr_t index) const { return nodes_[index]; }
+  void ReplaceNodeAt(intptr_t index, AstNode* value) { nodes_[index] = value; }
 
   DECLARE_COMMON_NODE_FUNCTIONS(SequenceNode);
 
   // Collects all nodes accessible from this sequence node into array 'nodes'.
   void CollectAllNodes(GrowableArray<AstNode*>* nodes);
 
  private:
   LocalScope* scope_;
   GrowableArray<AstNode*> nodes_;
   SourceLabel* label_;
@@ skipping 1625 matching lines @@
   const intptr_t try_index_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(InlinedFinallyNode);
 };
 
 }  // namespace dart
 
 #undef DECLARE_COMMON_NODE_FUNCTIONS
 
 #endif  // VM_AST_H_