Add layered buffer support to libui and libgui.

Bug: 31686534
Test: manual
Change-Id: Ia40270701467f4b785660324cad883e7da08989a
diff --git a/include/gui/GraphicBufferAlloc.h b/include/gui/GraphicBufferAlloc.h
index 62e3877..b19a1ac 100644
--- a/include/gui/GraphicBufferAlloc.h
+++ b/include/gui/GraphicBufferAlloc.h
@@ -34,8 +34,9 @@
     GraphicBufferAlloc();
     virtual ~GraphicBufferAlloc();
     virtual sp<GraphicBuffer> createGraphicBuffer(uint32_t width,
-            uint32_t height, PixelFormat format, uint32_t usage,
-            std::string requestorName, status_t* error) override;
+            uint32_t height, PixelFormat format, uint32_t layerCount,
+            uint32_t usage, std::string requestorName,
+            status_t* error) override;
 };