add point of interest API

experimental/skpdiff/SkPMetric.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 SkPMetric_DEFINED
 #define SkPMetric_DEFINED
 
+#include "SkTArray.h"
 #include "SkTDArray.h"
 
 #include "SkImageDiffer.h"
 
 /**
  * An image differ that uses the pdiff image metric to compare images.
  */
 class SkPMetric : public SkImageDiffer {
 public:
     virtual const char* getName() SK_OVERRIDE;
     virtual int queueDiff(SkBitmap* baseline, SkBitmap* test) SK_OVERRIDE;
+    virtual void deleteDiff(int id) SK_OVERRIDE;
     virtual bool isFinished(int id) SK_OVERRIDE;
     virtual double getResult(int id) SK_OVERRIDE;
+    virtual int getPointsOfInterestCount(int id) SK_OVERRIDE;
+    virtual SkIPoint* getPointsOfInterest(int id) SK_OVERRIDE;
 
 private:
     struct QueuedDiff {
         bool finished;
         double result;
+        SkTDArray<SkIPoint> poi;
     };
 
-    SkTDArray<QueuedDiff> fQueuedDiffs;
+    SkTArray<QueuedDiff> fQueuedDiffs;
 
     typedef SkImageDiffer INHERITED;
 };
 
 
 #endif