Pepper: Var keeps invalid var_id if VarTracker release it and there is another reference

ppapi/shared_impl/var.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PPAPI_SHARED_IMPL_VAR_H_
 #define PPAPI_SHARED_IMPL_VAR_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "ppapi/c/pp_var.h"
 #include "ppapi/shared_impl/ppapi_shared_export.h"
 
 namespace ppapi {
 
 class NPObjectVar;
 class ProxyObjectVar;
 class StringVar;
+class VarTracker;
 
 // Var -------------------------------------------------------------------------
 
 // Represents a non-POD var.
 class PPAPI_SHARED_EXPORT Var : public base::RefCounted<Var> {
  public:
   virtual ~Var();
 
   // Returns a string representing the given var for logging purposes.
   static std::string PPVarToLogString(PP_Var var);
@@ skipping 11 matching lines @@
 
   // Returns the ID corresponing to the string or object if it exists already,
   // or 0 if an ID hasn't been generated for this object (the plugin is holding
   // no refs).
   //
   // Contrast to GetOrCreateVarID which creates the ID and a ref on behalf of
   // the plugin.
   int32 GetExistingVarID() const;
 
  protected:
+  friend class VarTracker;
+
   Var();
 
   // Returns the unique ID associated with this string or object, creating it
   // if necessary. The return value will be 0 if the string or object is
   // invalid.
   //
   // This function will take a reference to the var that will be passed to the
   // caller.
   int32 GetOrCreateVarID();
 
   // Sets the internal object ID. This assumes that the ID hasn't been set
   // before. This is used in cases where the ID is generated externally.
   void AssignVarID(int32 id);
 
+  // Reset the assigned object ID.
+  void ResetVarID(void) { AssignVarID(0); };

[dmichael (off chromium), 2011/12/13 15:34:32]

nit: We don't normally put 'void' in the parameter list.

+
  private:
   // This will be 0 if no ID has been assigned (this happens lazily).
   int32 var_id_;
 
   DISALLOW_COPY_AND_ASSIGN(Var);
 };
 
 // StringVar -------------------------------------------------------------------
 
 // Represents a string-based Var.
@@ skipping 34 matching lines @@
 
  private:
   std::string value_;
 
   DISALLOW_COPY_AND_ASSIGN(StringVar);
 };
 
 }  // namespace ppapi
 
 #endif  // PPAPI_SHARED_IMPL_VAR_H_