Changed 'Android' icon to generic 'File' icon in attachment.

        ImageView thumbnailView = (ImageView) findViewById(R.id.attachment_icon);

        Glide.with(getContext())

                .load(attachment.internalUri)

                .placeholder(R.drawable.attached_image_placeholder)

                .placeholder(R.drawable.ic_file_light)

                .centerCrop()

                .into(thumbnailView);

    }