minor regex cleanup

[danmoseley]

some odds and ends from old branches.

1. remove dead string
2. improve node description
3. improve assertion message
4. inline some methods for clarity/consistency
5. improve intellisense for regexrunner fields
6. spacing some comments.
7. rename a method to match its job
8. add a couple tests (the bug they were for is gone, but they seem to fit)

[ghost]

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Issue Details

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1. remove dead string
2. improve node description
3. improve assertion message
4. inline some methods for clarity/consistency
5. improve intellisense for regexrunner fields
6. spacing some comments.
7. rename a method to match its job
8. add a couple tests (the bug they were for is gone, but they seem to fit)

Author:	danmoseley
Assignees:	danmoseley
Labels:	area-System.Text.RegularExpressions
Milestone:	-

[danmoseley]

feedback addressed

[danmoseley]

@lewing the "wasm smoke" failed as below. not sure whether I should create an issue, as it's "smoke"

function[8227]:0x204ec5)\n    at mono_background_exec (http://127.0.0.1:36683/dotnet.native.wasm:wasm-function[746]:0x46fa6)\n    at Ts (http://127.0.0.1:36683/dotnet.runtime.js:3:63074)"
[22:00:06] fail: [out of order message from the browser]: http://127.0.0.1:36683/dotnet.runtime.js 2:36671 Uncaught ManagedError: Error: Assert failed: ES6 module ./fetchelper.js w…83/dotnet.native.wasm:wasm-function[2384]:0xc15fe
[22:00:06] info: smoke: FetchBackground 2 ManagedThreadId:19, SynchronizationContext: System.Runtime.InteropServices.JavaScript.JSSynchronizationContext
[22:00:06] info: smoke: FetchBackground 3A ManagedThreadId:19, SynchronizationContext: System.Runtime.InteropServices.JavaScript.JSSynchronizationContext
[22:00:06] info: smoke: FetchBackground 3B ManagedThreadId:19, SynchronizationContext: System.Runtime.InteropServices.JavaScript.JSSynchronizationContext
[22:00:06] info: smoke: FetchBackground 4 ManagedThreadId:19, SynchronizationContext: System.Runtime.InteropServices.JavaScript.JSSynchronizationContext
[22:00:06] info: smoke: FetchBackground 5 ManagedThreadId:19, SynchronizationContext: System.Runtime.InteropServices.JavaScript.JSSynchronizationContext
[22:00:06] info: http://127.0.0.1:36683/dotnet.runtime.js 2 Error: Assert failed: ES6 module ./fetchelper.js was not imported yet, please call JSHost.ImportAsync() first.
[22:00:06] info: http://127.0.0.1:36683/dotnet.runtime.js 2 MONO_WASM [0x2d94488]: Proxy of JS object with JSHandleandle 1 was still alive
[22:00:06] info: WASM EXIT 2
[22:00:06] info: Waiting to flush log messages with a timeout of 120 secs ..
[22:00:06] fail: [out of order message from the browser]: http://127.0.0.1:36683/dotnet.js 2:214 Uncaught ManagedError: Error: Assert failed: ES6 module ./fetchelper.js w…83/dotnet.native.wasm:wasm-function[2384]:0xc15fe
[22:00:06] fail: Application has finished with exit code HELP_SHOWN but 0 was expected
XHarness exit code: 71 (GENERAL_FAILURE)
/root/helix/work/workitem/e /root/helix/work/workitem/e