Exposes your tear-off interfaces.
A tear-off interface is implemented as a separate object that is instantiated every time the interface it represents is queried for. Typically, you build your interface as a tear-off if the interface is rarely used, since this saves a vtable pointer in every instance of your main object. The tear-off is deleted when its reference count becomes zero. The class implementing the tear-off should be derived from CComTearOffObjectBase and have its own COM map.
See COM_INTERFACE_ENTRY Macros for remarks about COM map entries.