Merging r339667:
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    r339667 | theraven | 2018-08-14 12:04:36 +0200 (Tue, 14 Aug 2018) | 11 lines
    
    Add a stub mangling for ObjC selectors in the Microsoft ABI.
    
    This mangling is used only for outlined SEH finally blocks, which have
    internal linkage.
    
    This fixes the failure of CodeGenObjC/2007-04-03-ObjcEH.m on builds with
    expensive checks enabled, on Windows.  This test should probably be
    specifying a triple: it currently picks up whatever the host environment
    is using.  Unfortunately, I have no idea what it is trying to test,
    because it contains no comments and predates Clang having working
    Objective-C IR generation.
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    llvm-svn: 340437