Unused interop code in System.Management

[mthalman]

The following types in https://github.com/dotnet/runtime/blob/98ac23212e6017c615e7e855e676fc43c8e44cb8/src/libraries/System.Management/src/System/Management/InteropClasses/WMIInterop.cs are unused and should be removed. One of the issues with having this code is that it leads to incorrect assumptions of what native dependencies the codebase has (part of dotnet/core#5651).

• IWbemLocator
• WbemLocator
• IWbemServices_Old
• IWbemShutdown
• IUnsecuredApartment
• UnsecuredApartment
• IWbemPropertyProvider
• IWbemEventProvider
• IWbemEventProviderQuerySink
• IWbemEventProviderSecurity
• IWbemProviderIdentity
• IWbemEventConsumerProvider
• IWbemProviderInit
• IWbemProviderInitSink
• WbemDecoupledRegistrar
• IWbemDecoupledRegistrar
• MofCompiler
• WbemBackupRestore
• WbemDecoupledBasicEventProvider
• WbemQuery

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[hrrrrustic]

@danmoseley Uh, you've already picked this one :)

[hrrrrustic]

Will you close it or I can submit PR? 😄

[danmoseley]

I'll have a PR up in a moment. Just an easy one to do between meetings 😄

[danmoseley]

Oh, I see you already did it. Well, I'll just push up the PR since I said I'd do it now. thanks though!