Macro attributes are not recorded in GetCustomAttributes metadata

[masonwheeler]

• Create a class with a method
• Add an attribute to the method that is a macro attribute (one that applies a macro at compile-time)
• Create a second method that does the following:

       asm = Assembly.GetAssembly(self.GetType())
       methods = asm.GetTypes().SelectMany({t as Type | t.GetMethods()})
       applied = methods.Where({m as MethodInfo | m.GetCustomAttributes(MyMacroAttribute, false).Any()}).ToArray()

Expected: The applied array should contain the method with the macro applied to it. Observed: The applied array is empty.