ARROW-5714: [JS] Inconsistent behavior in Int64Builder with/without BigNum

[TheNeuralBit]

• Use stride in DataBufferBuilder.set to ensure that Int64Builder is consistent with and without BigNum.
• Use WideBufferBuilder for Int64 and Uint64 builders, even when BigInt is not available. Moves check for BigInt availability into WideBufferBuilder. (Thanks to Paul Taylor)

[trxcllnt]

@TheNeuralBit I was thinking about this more last night, and while this works for the JS-number case, it won't work if we try to set in a pair of [lo,hi]. So my thought was we should refactor the WideBufferBuilder so we could use it for the 64bit types, and just provide the BigInt TypedArray views if they're available.

[trxcllnt]

@TheNeuralBit TheNeuralBit#3 here's a pull that should do what we want in FF

[codecov-io]

Codecov Report

Merging #4691 into master will increase coverage by 1.25%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master   #4691      +/-   ##
=========================================
+ Coverage   88.94%   90.2%   +1.25%     
=========================================
  Files         705     101     -604     
  Lines       81275    6399   -74876     
  Branches     1420    1420              
=========================================
- Hits        72288    5772   -66516     
+ Misses       8977     617    -8360     
  Partials       10      10

Impacted Files	Coverage Δ
js/src/builder/buffer.ts	91.48% <100%> (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
r/src/symbols.cpp
cpp/src/arrow/io/test-common.h
cpp/src/arrow/util/int-util-test.cc
cpp/src/parquet/column_scanner.cc
r/R/ArrayData.R
... and 595 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 0568544...3688820. Read the comment docs.

[TheNeuralBit]

@trxcllnt I merged your PR and also clarified the int64 generation for the builder tests. Does this look ok to you?

[trxcllnt]

@TheNeuralBit yep, that looks great. thanks!