SkPDF: clean up extra references

src/pdf/SkPDFResourceDict.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPDFResourceDict_DEFINED
 #define SkPDFResourceDict_DEFINED
 
@@ skipping 60 matching lines @@
      *  the input key.
      *  The object will NOT be part of the resource list when requested later.
      *  @param type  The type of resource being entered.
      *  @param key   The resource key, should be unique within its type.
      *  @param value The resource itself.
      *  @return The value argument is returned.
      */
     SkPDFObject* insertResource(SkPDFResourceType type, int key,
                                 SkPDFObject* value);
 
-    SkTSet<SkPDFObject*> fResources;
-
     SkTDArray<SkPDFDict*> fTypes;
     typedef SkPDFDict INHERITED;
 };
 
 #endif