ARROW-4682: [JS] Fix writing empty tables

[trxcllnt]

Closes https://issues.apache.org/jira/browse/ARROW-4682

[TheNeuralBit]

Can you re-run CI?

No output has been received in the last 10m0s, this potentially indicates a stalled build or something wrong with the build itself.
Check the details on how to adjust your build configuration on: https://docs.travis-ci.com/user/common-build-problems/#Build-times-out-because-no-output-was-received

I've seen this a couple of times now... are we up against some free tier limit or can we fix this with a config change? @wesm do you know?

[codecov-io]

Codecov Report

Merging #3759 into master will increase coverage by 2.84%.
The diff coverage is 89.18%.

@@            Coverage Diff             @@
##           master    #3759      +/-   ##
==========================================
+ Coverage   87.57%   90.41%   +2.84%     
==========================================
  Files         533       74     -459     
  Lines       60623     5434   -55189     
  Branches        0     1234    +1234     
==========================================
- Hits        53088     4913   -48175     
+ Misses       7430      513    -6917     
+ Partials      105        8      -97

Impacted Files	Coverage Δ
js/src/util/recordbatch.ts	98.18% <100%> (ø)
js/src/table.ts	93.87% <100%> (ø)
js/src/visitor/vectorassembler.ts	82.69% <100%> (ø)
js/src/schema.ts	88.77% <100%> (ø)
js/src/ipc/writer.ts	88.99% <78.94%> (ø)
cpp/src/arrow/csv/chunker-test.cc
cpp/src/parquet/column_page.h
cpp/src/parquet/bloom_filter-test.cc
cpp/src/arrow/array/builder_decimal.cc
cpp/src/plasma/client.cc
... and 602 more

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[trxcllnt]

@TheNeuralBit I rebased from master and that seemed to fix the Python 2.7/3.6 failure.

[TheNeuralBit]

👍

I wrote up https://issues.apache.org/jira/browse/ARROW-4695 to track the CI failure. It looks like the build is actually stalling for some reason.