miniobject: delay private data initialisation until actually needed
miniobject: delay private data initialisation until actually needed

We only use the private instance data for weak references for now,
so can delay initialisation until actually needed (microoptimisation)

justinjoy/gstreamer,Distrotech/gstreamer,surround-io/gstreamer,collects/gstreamer,ahmedammar/platform_external_gst_gstreamer,Lachann/gstreamer,Distrotech/gstreamer,mparis/gstreamer,krichter722/gstreamer,surround-io/gstreamer,collects/gstreamer,shelsonjava/gstreamer,krichter722/gstreamer,mparis/gstreamer,StreamUtils/gstreamer,drothlis/gstreamer,ensonic/gstreamer,jpakkane/gstreamer,ylatuya/gstreamer,jpxiong/gstreamer,magcius/gstreamer,jpxiong/gstreamer,drothlis/gstreamer,ylatuya/gstreamer,jpakkane/gstreamer,lubosz/gstreamer,collects/gstreamer,lovebug356/gstreamer,ahmedammar/platform_external_gst_gstreamer,cablelabs/gstreamer,cfoch/gstreamer,ahmedammar/platform_external_gst_gstreamer,Lachann/gstreamer,cablelabs/gstreamer,ylatuya/gstreamer,jpakkane/gstreamer,drothlis/gstreamer,cablelabs/gstreamer,lubosz/gstreamer,justinjoy/gstreamer,ylatuya/gstreamer,cablelabs/gstreamer,shelsonjava/gstreamer,surround-io/gstreamer,krieger-od/gstreamer,Distrotech/gstreamer,justinjoy/gstreamer,cfoch/gstreamer,ahmedammar/platform_external_gst_gstreamer,krichter722/gstreamer,mparis/gstreamer,shelsonjava/gstreamer,collects/gstreamer,lovebug356/gstreamer,StreamUtils/gstreamer,shelsonjava/gstreamer,krichter722/gstreamer,centricular/gstreamer,Lachann/gstreamer,centricular/gstreamer,mparis/gstreamer,collects/gstreamer,ensonic/gstreamer,Distrotech/gstreamer,ahmedammar/platform_external_gst_gstreamer,krieger-od/gstreamer,lubosz/gstreamer,mparis/gstreamer,StreamUtils/gstreamer,surround-io/gstreamer,ensonic/gstreamer,lovebug356/gstreamer,justinjoy/gstreamer,lovebug356/gstreamer,Distrotech/gstreamer,jpakkane/gstreamer,krieger-od/gstreamer,justinjoy/gstreamer,ensonic/gstreamer,StreamUtils/gstreamer,cablelabs/gstreamer,Lachann/gstreamer,ensonic/gstreamer,cfoch/gstreamer,jpxiong/gstreamer,jpxiong/gstreamer,surround-io/gstreamer,magcius/gstreamer,lubosz/gstreamer,lovebug356/gstreamer,Lachann/gstreamer,cfoch/gstreamer,jpakkane/gstreamer,drothlis/gstreamer,StreamUtils/gstreamer,centricular/gstreamer,centricular/gstreamer,magcius/gstreamer,lubosz/gstreamer,jpxiong/gstreamer,krieger-od/gstreamer,shelsonjava/gstreamer,ylatuya/gstreamer,cfoch/gstreamer,magcius/gstreamer,krieger-od/gstreamer,drothlis/gstreamer,magcius/gstreamer,centricular/gstreamer,krichter722/gstreamer