provide backward compatible send overload

[sergiud]

Fixes ceres-solver/ceres-solver#735

[codecov-commenter]

Codecov Report

Merging #763 (4765234) into master (d09b999) will decrease coverage by 0.24%.
The diff coverage is 58.82%.

@@            Coverage Diff             @@
##           master     #763      +/-   ##
==========================================
- Coverage   73.01%   72.77%   -0.25%     
==========================================
  Files          17       17              
  Lines        3217     3232      +15     
==========================================
+ Hits         2349     2352       +3     
- Misses        868      880      +12     

Impacted Files	Coverage Δ
src/utilities.h	100.00% <ø> (ø)
src/glog/logging.h.in	80.00% <50.00%> (-3.14%)	⬇️
src/logging.cc	73.49% <59.37%> (-0.38%)	⬇️

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