Remove commented out scalesystemdependent code.
Remove variance-invoke patch.

This issue is fixed in a different way upstream. To verify,
configure with RTCD, figure out how to turn on temporal layers in
WebRTC, and measure VP8 decoding performance.
Remove obsolete patch files.
cleanup moz.build/Makefile.in

 - add newlines
 - move all .c files to moz.build
 - use $(OBJ_SUFFIX)