The exact messages depend on the timing of several events and may vary
between runs. This occasionally causes flakes on CI.
This commit reduces the risk of flakes by loosen the conditions to only
check for what we actually care about.
Fixes#29544
PR Close#29757
Clearing array with setting length to 0 replaced with [] for being short
and marginally efficient. For reference: [] is turned into a sequence of
around 15 machine instructions on x64 (if bump pointer allocation succeeds),
whereas a.length=0 is a C++ runtime function call, which requires 10-100x as
many instructions.
Benedikt Meurer
PR Close#20395