Fix parsing of dimensions without a unit specifier.
Fix parsing of dimensions without a unit specifier.

svn path=/trunk/libcss/; revision=6088

prepare/netsurf_libcss,servo/libcss,servo/libcss,servo/libcss,zhuyadong/libcss,zhuyadong/libcss,zhuyadong/libcss,prepare/netsurf_libcss,prepare/netsurf_libcss