byteArray: Add compatibility toString property

This overrides, on each Uint8Array returned from an introspected function
or from ByteArray.fromString() or ByteArray.fromGBytes(), the toString()
property with a compatibility shim that preserves the old behaviour of
ByteArray.prototype.toString() while logging a compatibility warning
asking people to fix their code.

This ByteArray.toString() -> Uint8Array.toString() change has had more
fallout in application code than I expected, so it seems better to
preserve backwards compatibility. (The old behaviour was to decode the
byte array into a string with default encoding UTF-8, and the default
behaviour of Uint8Array is to return a string with the decimal digits of
each byte joined with commas. So the effect was that strings like
"97,98,99,100" would show up in UIs where previously "abcd" would have
been printed.

This is only on specific instances, so Uint8Array.prototype.toString()
remains untouched.
27 jobs for compatibility-bytearray-tostring in 42 minutes and 7 seconds (queued for 5 minutes and 6 seconds)
Status Job ID Name Coverage
  Source Check
passed #87454
cppcheck

00:00:43

passed #87455
cpplint

00:01:09

passed #87456
eslint

00:00:51

passed #87453
fedora

00:02:41

 
  Test
passed #87459
no_graphics

00:02:05

passed #87460
no_profiler

00:02:16

passed #87461
no_readline

00:02:14

passed #87457
sanitizer_gcc

00:03:37

passed #87458
with_logging

00:02:41

 
  Manual
manual #87475
allowed to fail manual
armv8
manual #87462
allowed to fail manual
codequality
manual #87463
allowed to fail manual
code_statistics
passed #87477
manual
coverage

00:02:30

passed #87465
manual
fedora_gcc

00:05:33

manual #87471
allowed to fail manual
flatpak
passed #93207
manual
installed_tests

00:02:14

manual #87469
allowed to fail manual
lts
manual #87476
allowed to fail manual
ppc64le
passed #87464
manual
sanitizer_clang

00:03:20

passed #87468
manual
ubuntu_clang

00:05:04

passed #87467
manual
ubuntu_gcc

00:05:03

manual #87470
allowed to fail manual
valgrind
manual #87474
allowed to fail manual
zeal_11
manual #87472
allowed to fail manual
zeal_2
manual #87473
allowed to fail manual
zeal_4
failed #87466
allowed to fail manual
installed_tests

00:00:09

failed #92505
allowed to fail manual
installed_tests

00:00:09