diff --git a/include/gui/BufferItem.h b/include/gui/BufferItem.h
index c7a8bc9..112c482 100644
--- a/include/gui/BufferItem.h
+++ b/include/gui/BufferItem.h
@@ -44,6 +44,7 @@
     // The default value of mBuf, used to indicate this doesn't correspond to a slot.
     enum { INVALID_BUFFER_SLOT = -1 };
     BufferItem();
+    BufferItem(const IGraphicBufferConsumer::BufferItem& item);
     ~BufferItem();
     operator IGraphicBufferConsumer::BufferItem() const;
 
@@ -86,8 +87,13 @@
     // mFrameNumber is the number of the queued frame for this slot.
     uint64_t mFrameNumber;
 
-    // mSlot is the slot index of this buffer (default INVALID_BUFFER_SLOT).
-    int mSlot;
+    union {
+        // mSlot is the slot index of this buffer (default INVALID_BUFFER_SLOT).
+        int mSlot;
+
+        // mBuf is the former name for mSlot
+        int mBuf;
+    };
 
     // mIsDroppable whether this buffer was queued with the
     // property that it can be replaced by a new buffer for the purpose of