Creating Transparent EGL surface

Question

I am playing tunneling video from a video player app. When the app is launched video will be played in a sideband stream and played in videoplane. Graphics plane will be on top of video plane. I need to make graphics layer transparent to overlay volume and other settings on top of video. To achieve this am trying to make the EGL surface on which graphics is rendered to transparent with the below config.

static const EGLint kEGLConfigAttribsRGBA32[] = 
{
     LOCAL_EGL_RENDERABLE_TYPE, LOCAL_EGL_OPENGL_ES2_BIT,
     LOCAL_EGL_SURFACE_TYPE, LOCAL_EGL_WINDOW_BIT,
     LOCAL_EGL_TRANSPARENT_TYPE, LOCAL_EGL_TRANSPARENT_RGB,
     LOCAL_EGL_COLOR_BUFFER_TYPE,LOCAL_EGL_RGB_BUFFER,
     LOCAL_EGL_RED_SIZE,     8,
     LOCAL_EGL_GREEN_SIZE,   8,
     LOCAL_EGL_BLUE_SIZE,    8,
     LOCAL_EGL_ALPHA_SIZE,   8,
     LOCAL_EGL_DEPTH_SIZE,   16
};

But with this config egl surface is not getting created am not seeing anything on display. Instead its all cluttered lines on display.

Can anyone please help in making EGL surface transparent? Am using gecko code of firefox with native platform as android