DateTimeFormatInfo.GetEra(string) does not work in a scenario

[alexeysmorkalov]

DateTimeFormatInfo.GetEra(string) always returns -1 if you pass abbreviated english era name as input parameter

Steps to reproduce

            var ci = new CultureInfo("ja-JP") { DateTimeFormat = { Calendar = new JapaneseCalendar() }};
            var jpFormatInfo = ci.DateTimeFormat;

            // it returns -1 but expected 4
              var result = jpFormatInfo.GetEra("H");

Configuration

Fails on 5.0.100-preview.7.20366.6
Works correctly on any .NET Framework, .Net Core 3.0, .Net Core 3.1, .Net 5 lower than 5.0.100-preview.4.20258.7
x64

Regression

.Net Framework, Core 3.0, Core 3.1 and .Net5 until 5.0.100-preview.4.20258.7

Other information

The reason is System.Globalization.DateTimeFormatInfo.AbbreviatedEnglishEraNames contains not abbreviated but full era names

[ghost]

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[tarekgh]

Thanks @alexeysmorkalov for reporting the issue. we'll take a look to see what is going on.