fix pooled array leak

[danmoseley]

I ran the tests with some rudimentary tracing on the array pool and found one leak.

1. fix leak in FileSystemName.cs
2. fix some of the leaks in tests that were particularly noisy in the logs. Happy to revert some or all of these.

[ghost]

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Issue Details

---

I ran the tests with some rudimentary tracing on the array pool and found one leak.

1. fix leak in FileSystemName.cs
2. fix some of the leaks in tests that were particularly noisy in the logs. Happy to revert some or all of these.

Author:	danmoseley
Assignees:	danmoseley
Labels:	area-System.IO
Milestone:	-

[danmoseley]

I'll close until I've finished.

[danmoseley]

OK hopefully ready for review now.

[danmoseley]

03:19:50] info: Starting:    managed/System.Collections.Tests.dll
[03:21:00] info: Error: failed to run main module `dotnet.wasm`
[03:21:00] info: 
[03:21:00] info: Caused by:
[03:21:00] info:     0: failed to invoke command default
[03:21:00] info:     1: error while executing at wasm backtrace:
[03:21:00] info:            0: 0x56e9c - <unknown>!drain_gray_stack
[03:21:00] info:            1: 0x4cc5a - <unknown>!sgen_drain_gray_stack
[03:21:00] info:            2: 0x10e3b1 - <unknown>!sgen_client_mark_togglerefs
[03:21:00] info:            3: 0x50ffb - <unknown>!finish_gray_stack
[03:21:00] info:            4: 0x4df21 - <unknown>!major_do_collection
[03:21:00] info:            5: 0x4d322 - <unknown>!sgen_perform_collection
[03:21:00] info:            6: 0x4d186 - <unknown>!sgen_ensure_free_space
[03:21:00] info:            7: 0x53eea - <unknown>!sgen_los_alloc_large_inner
[03:21:00] info:            8: 0x4be31 - <unknown>!sgen_alloc_obj_nolock
[03:21:00] info:            9: 0x10ffda - <unknown>!mono_gc_alloc_vector
[03:21:00] info:           10: 0xe9c6a - <unknown>!mono_array_new_specific_internal
[03:21:00] info:           11: 0xe9caf - <unknown>!mono_array_new_specific_checked
[03:21:00] info:           12: 0x10dbd - <unknown>!mono_interp_exec_method
[03:21:00] info:           13: 0x7f21 - <unknown>!interp_runtime_invoke
[03:21:00] info:           14: 0x11e6e3 - <unknown>!mono_jit_runtime_invoke
[03:21:00] info:           15: 0xe286b - <unknown>!do_runtime_invoke
[03:21:00] info:           16: 0xe2812 - <unknown>!mono_runtime_invoke_checked
[03:21:00] info:           17: 0xe91e7 - <unknown>!mono_runtime_try_invoke_byrefs
[03:21:00] info:           18: 0xafbe4 - <unknown>!ves_icall_InternalInvoke
[03:21:00] info:           19: 0xb8413 - <unknown>!ves_icall_InternalInvoke_raw
[03:21:00] info:           20: 0x19bf1 - <unknown>!do_icall
[03:21:00] info:           21: 0x188d0 - <unknown>!do_icall_wrapper
[03:21:00] info:           22: 0x9283 - <unknown>!mono_interp_exec_method
[03:21:00] info:           23: 0x7f21 - <unknown>!interp_runtime_invoke
[03:21:00] info:           24: 0x11e6e3 - <unknown>!mono_jit_runtime_invoke
[03:21:00] info:           25: 0xe286b - <unknown>!do_runtime_invoke
[03:21:00] info:           26: 0xe3205 - <unknown>!mono_runtime_try_invoke
[03:21:00] info:           27: 0xe7a48 - <unknown>!do_try_exec_main
[03:21:00] info:           28: 0xe74e7 - <unknown>!mono_runtime_run_main
[03:21:00] info:           29: 0x694d - <unknown>!main
[03:21:00] info:           30: 0x27375c - <unknown>!__main_void
[03:21:00] info:           31: 0x59b2 - <unknown>!_start
[03:21:00] info:           32: 0x28693e - <unknown>!_start.command_export
[03:21:00] info:        note: using the `WASMTIME_BACKTRACE_DETAILS=1` 

[danmoseley]

Any other feedback @stephentoub