[perl #125891] When class D::E is defined before class D, having just one of them declared in 'my' scope apparently erases D::E

[via RT]

# New Ticket Created by  Faye 
# Please include the string:  [perl #125891]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=125891 >


    $ perl6 -e 'class D::E { method foo { "foo" } }; class D { method bar { 
"bar" } }; say D.bar; say D::E.foo'
    bar
    foo
    $ perl6 -e 'my class D::E { method foo { "foo" } }; class D { method bar { 
"bar" } }; say D.bar; say D::E.foo'
    bar
    Could not find symbol '&E'
      in block <unit> at -e:1

    Actually thrown at:
      in block <unit> at -e:1
    $ perl6 -e 'class D::E { method foo { "foo" } }; my class D { method bar { 
"bar" } }; say D.bar; say D::E.foo'
    bar
    Could not find symbol '&E'
      in block <unit> at -e:1

    Actually thrown at:
      in block <unit> at -e:1
    $ perl6 -e 'my class D::E { method foo { "foo" } }; my class D { method bar 
{ "bar" } }; say D.bar; say D::E.foo'
    bar
    Could not find symbol '&E'
      in block <unit> at -e:1

    Actually thrown at:
      in block <unit> at -e:1

But put D before D::E :

    $ perl6 -e 'class D { method bar { "bar" } }; class D::E { method foo { 
"foo" } };  say D.bar; say D::E.foo'
    bar
    foo
    $ perl6 -e 'my class D { method bar { "bar" } }; class D::E { method foo { 
"foo" } };  say D.bar; say D::E.foo'
    bar
    foo
    $ perl6 -e 'class D { method bar { "bar" } }; my class D::E { method foo { 
"foo" } };  say D.bar; say D::E.foo'
    bar
    foo
    $ perl6 -e 'my class D { method bar { "bar" } }; my class D::E { method foo 
{ "foo" } };  say D.bar; say D::E.foo'
    bar
    foo

As discovered by YuriPanda at 
http://irclog.perlgeek.de/perl6/2015-08-24#i_11109804 , what's shown above 
appears to be the root of the issue.