Return 'correct' size from GrMemoryPool

src/gpu/GrMemoryPool.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrMemoryPool_DEFINED
 #define GrMemoryPool_DEFINED
 
@@ skipping 26 matching lines @@
      * p must have been returned by allocate()
      */
     void release(void* p);
 
     /**
      * Returns true if there are no unreleased allocations.
      */
     bool isEmpty() const { return fTail == fHead && !fHead->fLiveCount; }
 
     /**
-     * Returns the total allocated size of the GrMemoryPool
+     * Returns the total allocated size of the GrMemoryPool minus any preallocated amount
      */
     size_t size() const { return fSize; }
 
 private:
     struct BlockHeader;
 
     static BlockHeader* CreateBlock(size_t size);
 
     static void DeleteBlock(BlockHeader* block);
 
@@ skipping 21 matching lines @@
     size_t                            fMinAllocSize;
     BlockHeader*                      fHead;
     BlockHeader*                      fTail;
 #ifdef SK_DEBUG
     int                               fAllocationCnt;
     int                               fAllocBlockCnt;
 #endif
 };
 
 #endif