Update the maximum message length in the EventLog.WriteEntry method documentation

[0xced]

Summary

It was found empirically on Windows 10 that the maximum message length is 31,718.

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Tagging subscribers to this area: @tommcdon

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[gewarren]

@tommcdon Could you review?

[tommcdon]

.NET is using ReportEvent, and according to the Windows documentation for ReportEvent, our existing documentation is correct:

https://learn.microsoft.com/windows/win32/api/winbase/nf-winbase-reporteventw

[in] lpStrings
A pointer to a buffer containing an array of null-terminated strings that are merged into the message before Event Viewer displays the string to the user. This parameter must be a valid pointer (or NULL), even if wNumStrings is zero. Each string is limited to 31,839 characters.
Prior to Windows Vista:  Each string is limited to 32K characters.

The .NET code that calls ReportEvent is checking 32K-2 characters:

https://github.com/dotnet/runtime/blob/c1a9f26efa4fcf2e3fdcd8557da19d358f51eb00/src/libraries/System.Diagnostics.EventLog/src/System/Diagnostics/EventLogInternal.cs#L1354-L1357

                // make sure the strings aren't too long.  MSDN says each string has a limit of 32k (32768) characters, but
                // experimentation shows that it doesn't like anything larger than 32766
                if (strings[i].Length > 32766)
                    throw new ArgumentException(SR.LogEntryTooLong);

Therefore, the error would likely be coming from Windows and not .NET for string lengths <= 32766 characters. Given that .NET has no control over the version of Windows and the various character limits it is imposing, I suggest we remove mentions of specific character limits under 32766 characters.

Also I would expect that if the string length is <= 32766 and the API call fails due to a restriction from Windows, we would get a Win32Exception and not an ArgumentException. @0xced can you confirm?

If yes, then I suggest changing the text to something like:
The message string is longer than 32,766 bytes.

[tommcdon]

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