[server] Provide wl_resource *resource() in BufferInterface

We need to be able to access the wl_resource* to bind it to a texture.

src/wayland/server/buffer_interface.cpp

@@ -186,5 +186,10 @@ wl_shm_buffer *BufferInterface::shmBuffer()
     return d->shmBuffer;
 }
 
+wl_resource *BufferInterface::resource() const
+{
+    return d->buffer;
+}
+
 }
 }

src/wayland/server/buffer_interface.h

@@ -46,6 +46,7 @@ public:
 
     SurfaceInterface *surface() const;
     wl_shm_buffer *shmBuffer();
+    wl_resource *resource() const;
 
     /**
      * Creates a QImage for the shared memory buffer.