Revert "get rid of IGraphicBufferAlloc"

This reverts commit 1da94dfed674e94edc37cdc8ef68530520edf169.

Bug: 36176799
Bug: 36175706
Change-Id: I6dd5fe8df564f0efa4392a800fb316e27a05076e
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 6ce799a..d63c0bb 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -76,6 +76,7 @@
 class Client;
 class DisplayEventConnection;
 class EventThread;
+class IGraphicBufferAlloc;
 class Layer;
 class LayerDim;
 class Surface;
@@ -202,6 +203,7 @@
      */
     virtual sp<ISurfaceComposerClient> createConnection();
     virtual sp<ISurfaceComposerClient> createScopedConnection(const sp<IGraphicBufferProducer>& gbp);
+    virtual sp<IGraphicBufferAlloc> createGraphicBufferAlloc();
     virtual sp<IBinder> createDisplay(const String8& displayName, bool secure);
     virtual void destroyDisplay(const sp<IBinder>& display);
     virtual sp<IBinder> getBuiltInDisplay(int32_t id);