Creating small arrays is slower in 1.0 (compared to 0.6)

[ViralBShah]

Benchmarking small array creation using ones (size 1 and 10) 0.6.4 vs. 1.0.3 suggests that it is about 15% slower in 1.0.

julia> versioninfo()
Julia Version 0.6.4
Commit 9d11f62bcb (2018-07-09 19:09 UTC)
Platform Info:
  OS: macOS (x86_64-apple-darwin14.5.0)
  CPU: Intel(R) Core(TM) i5-7360U CPU @ 2.30GHz
  WORD_SIZE: 64
  BLAS: libopenblas (USE64BITINT DYNAMIC_ARCH NO_AFFINITY Haswell MAX_THREADS=16)
  LAPACK: libopenblas64_
  LIBM: libopenlibm
  LLVM: libLLVM-3.9.1 (ORCJIT, broadwell)

julia> @btime ones(1);
  25.919 ns (1 allocation: 96 bytes)

julia> @btime ones(10);
  29.851 ns (1 allocation: 160 bytes)

julia> versioninfo()
Julia Version 1.0.3
Commit 099e826241 (2018-12-18 01:34 UTC)
Platform Info:
  OS: macOS (x86_64-apple-darwin14.5.0)
  CPU: Intel(R) Core(TM) i5-7360U CPU @ 2.30GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-6.0.0 (ORCJIT, skylake)

julia> @btime ones(1);
  30.834 ns (1 allocation: 96 bytes)

julia> @btime ones(10);
  34.186 ns (1 allocation: 160 bytes)

[ViralBShah]

@vtjnash @JeffBezanson I am guessing there's not much to do here. Should we close? The performance here for 1.0.x and 1.6-master is the same.