Add integration of the new heuristics

components/dom_distiller/core/distillable_page_detector.h

 // Copyright 2015 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 COMPONENTS_DOM_DISTILLER_CORE_DISTILLABLE_PAGE_DETECTOR_H_
 #define COMPONENTS_DOM_DISTILLER_CORE_DISTILLABLE_PAGE_DETECTOR_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "components/dom_distiller/core/proto/adaboost.pb.h"
 
 namespace dom_distiller {
 
 class DistillablePageDetector {
  public:
+  static const DistillablePageDetector* GetDefault();
   explicit DistillablePageDetector(scoped_ptr<AdaBoostProto> proto);
   ~DistillablePageDetector();
   bool Classify(const std::vector<double>& features) const;
   double Score(const std::vector<double>& features) const;
   double GetThreshold() const;
  private:
   scoped_ptr<AdaBoostProto> proto_;
   double threshold_;
   DISALLOW_COPY_AND_ASSIGN(DistillablePageDetector);
 };
 
 
 }  // namespace dom_distiller
 
 #endif  // COMPONENTS_DOM_DISTILLER_CORE_DISTILLABLE_PAGE_DETECTOR_H_