always use GL_RGBA, GL_UNSIGNED_BYTE for screen capture and make sure to handle GL_BGRA_EXT used on some gpu. Change-Id: If9c973677fec8a5c4e72be22e7ef7d4bf5f008f4
Change-Id: Ibf07eff68d39267fd5c9bec2870f59a5ae2f51e3