Forward compatibility patch.

Change-Id: I8e8af0c6035aaac5e5097f1cfb198250475627ee
diff --git a/include/gui/ISurfaceComposer.h b/include/gui/ISurfaceComposer.h
index 7320e4d..09e7771 100644
--- a/include/gui/ISurfaceComposer.h
+++ b/include/gui/ISurfaceComposer.h
@@ -96,6 +96,10 @@
         eElectronBeamAnimationOff = 0x10
     };
 
+    enum {
+        eDisplayIdMain = 0
+    };
+
     /* create connection with surface flinger, requires
      * ACCESS_SURFACE_FLINGER permission
      */