Provide an option in bench_pictures to count pixel ram.

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
 
@@ skipping 10 matching lines @@
 
 public:
     SkLruImageCache(size_t budget);
 
     virtual ~SkLruImageCache();
 
 #ifdef SK_DEBUG
     CacheStatus getCacheStatus(intptr_t ID) const SK_OVERRIDE;
 #endif
 
-    void setBudget(size_t newBudget);
+    /**
+     *  Set the byte limit on cached pixels. If more bytes are used than this, the cache will free
+     *  unpinned memory until under the new limit or until all unpinned memory is freed. This will
+     *  never free pinned memory, so the cache can potentially remain over the limit. The limit is
+     *  enforced each time memory is allocated or released.
+     *  0 is a special flag for an infinite budget.
+     *  @return size_t The previous limit.
+     */
+    size_t setImageCacheLimit(size_t newLimit);
+
+    /**
+     *  Return the number of bytes of memory currently in use by the cache. Can include memory that
+     *  is no longer pinned, but has not been freed.
+     */
+    size_t getImageCacheUsed() const { return fRamUsed; }
 
     virtual void* allocAndPinCache(size_t bytes, intptr_t* ID) SK_OVERRIDE;
     virtual void* pinCache(intptr_t ID) SK_OVERRIDE;
     virtual void releaseCache(intptr_t ID) SK_OVERRIDE;
     virtual void throwAwayCache(intptr_t ID) SK_OVERRIDE;
 
 private:
     // Linked list of recently used. Head is the most recently used, and tail is the least.
     SkTInternalLList<CachedPixels> fLRU;
     typedef SkTInternalLList<CachedPixels>::Iter Iter;
@@ skipping 23 matching lines @@
      */
     void purgeTilAtOrBelow(size_t limit);
 
     /**
      *  Remove a set of CachedPixels. Mutex must be locked before calling.
      */
     void removePixels(CachedPixels*);
 };
 
 #endif // SkLruImageCache_DEFINED