Try to fix compilation error on Android (#2187)

* Try to fix compilation error on Android

* Try with a newer NDK...

build/android/build.sh

@@ -11,8 +11,8 @@
 set -e
 set -x
 
-NDK_VERSION="ndk;20.0.5594570"
-ANDROID_NDK_VERSION=20
+NDK_VERSION="ndk;21.0.6113669"
+ANDROID_NDK_VERSION=21
 
 UNAME=`echo $(uname)`
 LC_UNAME=`echo $UNAME | tr '[:upper:]' '[:lower:]'`

libs/geometry/include/geometry/SurfaceOrientation.h

@@ -21,6 +21,8 @@
 #include <math/vec3.h>
 #include <math/vec4.h>
 
+#include <utils/compiler.h>
+
 namespace filament {
 
 /**
@@ -34,7 +36,7 @@ struct OrientationImpl;
 /**
  * The surface orientation helper can be used to populate Filament-style TANGENTS buffers.
  */
-class SurfaceOrientation {
+class UTILS_PUBLIC SurfaceOrientation {
 public:
 
     /**