Android: called unimplemented OpenGL ES API

[gpempro]

PrimitiveBatch.cs triggers plenty of: E/libEGL ( 3260): called unimplemented OpenGL ES API

More precisely, the following calls trigger these exceptions:

• basicEffect.CurrentTechnique.Passes[0].Apply();
• device.DrawUserPrimitives(primitiveType, vertices, 0, primitiveCount);