SF: replicate mActiveBuffer in LayerBE as mBuffer

Replicate mAcitveBuffer in LayerBE as mBuffer

Test: build/run
Change-Id: Iaec4eeddbf4ca1798a47ecbb6c0b6c82ceb1d27c
diff --git a/services/surfaceflinger/Layer.h b/services/surfaceflinger/Layer.h
index b12e34f..8ac5094 100644
--- a/services/surfaceflinger/Layer.h
+++ b/services/surfaceflinger/Layer.h
@@ -70,6 +70,9 @@
 public:
     LayerBE();
 
+    // main thread
+    int mBufferSlot;
+    sp<GraphicBuffer> mBuffer;
     sp<NativeHandle> mSidebandStream;
 
     // The mesh used to draw the layer in GLES composition mode
@@ -469,8 +472,6 @@
     void setFiltering(bool filtering);
     bool getFiltering() const;
 
-    // only for debugging
-    inline const sp<GraphicBuffer>& getActiveBuffer() const { return mActiveBuffer; }
 
     inline const State& getDrawingState() const { return mDrawingState; }
     inline const State& getCurrentState() const { return mCurrentState; }