Introduce a SignatureData class so that signature functions can store both their

runtime/vm/snapshot.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 RUNTIME_VM_SNAPSHOT_H_
 #define RUNTIME_VM_SNAPSHOT_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
@@ skipping 59 matching lines @@
 class RawBigint;
 class RawNamespace;
 class RawObject;
 class RawObjectPool;
 class RawOneByteString;
 class RawPatchClass;
 class RawPcDescriptors;
 class RawReceivePort;
 class RawRedirectionData;
 class RawScript;
+class RawSignatureData;
 class RawSendPort;
 class RawSmi;
 class RawStackMap;
 class RawStackTrace;
 class RawSubtypeTestCache;
 class RawTokenStream;
 class RawTwoByteString;
 class RawType;
 class RawTypeArguments;
 class RawTypedData;
@@ skipping 445 matching lines @@
   friend class Library;
   friend class LibraryPrefix;
   friend class LinkedHashMap;
   friend class LiteralToken;
   friend class MirrorReference;
   friend class MixinAppType;
   friend class Namespace;
   friend class PatchClass;
   friend class RedirectionData;
   friend class Script;
+  friend class SignatureData;
   friend class SubtypeTestCache;
   friend class TokenStream;
   friend class Type;
   friend class TypeArguments;
   friend class TypeParameter;
   friend class TypeRef;
   friend class UnhandledException;
   friend class UnresolvedClass;
   friend class WeakProperty;
   DISALLOW_COPY_AND_ASSIGN(SnapshotReader);
@@ skipping 461 matching lines @@
  private:
   SnapshotWriter* writer_;
   bool as_references_;
 
   DISALLOW_COPY_AND_ASSIGN(SnapshotWriterVisitor);
 };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_SNAPSHOT_H_