Return 'correct' size from GrMemoryPool

src/gpu/GrMemoryPool.h

Index: src/gpu/GrMemoryPool.h
diff --git a/src/gpu/GrMemoryPool.h b/src/gpu/GrMemoryPool.h
index 4de641d9fcb31327535762a79b0528803a6d9701..5e38a29c041d730259fc273cec60abc2c960cf05 100644
--- a/src/gpu/GrMemoryPool.h
+++ b/src/gpu/GrMemoryPool.h
@@ -44,7 +44,7 @@ public:
     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; }