Fix two leaks & improve leak tracking

include/lazy/SkLruImageCache.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 SkLruImageCache_DEFINED
 #define SkLruImageCache_DEFINED
 
 #include "SkImageCache.h"
 #include "SkThread.h"
 #include "SkTInternalLList.h"
 
 class CachedPixels;
 
 /**
  *  SkImageCache implementation that uses an LRU cache to age out old images.
  */
 class SkLruImageCache : public SkImageCache {
 
 public:
+    SK_DECLARE_INST_COUNT(SkLruImageCache)
+
     SkLruImageCache(size_t budget);
 
     virtual ~SkLruImageCache();
 
 #ifdef SK_DEBUG
     virtual MemoryStatus getMemoryStatus(ID) const SK_OVERRIDE;
     virtual void purgeAllUnpinnedCaches() SK_OVERRIDE;
 #endif
 
     /**
@@ skipping 47 matching lines @@
      */
     void purgeTilAtOrBelow(size_t limit);
 
     /**
      *  Remove a set of CachedPixels. Mutex must be locked before calling.
      */
     void removePixels(CachedPixels*);
 };
 
 #endif // SkLruImageCache_DEFINED