convert(::Type{BigFloat}, ...) uses the current rounding mode, shouldn't it instead always use RoundNearest?

[nsajko]

julia> setprecision(BigFloat, 4) do
           (
               setrounding(BigFloat, RoundDown) do
                   convert(BigFloat, 1/3)
               end,
               setrounding(BigFloat, RoundUp) do
                   convert(BigFloat, 1/3)
               end,
           )
       end
(0.312, 0.344)

julia> ==(ans...)
false

I think it'd make more sense for convert(::Type{BigFloat}, ::Any) not to depend on the current rounding mode. It could always use RoundNearest, no? Would that be a breaking change?