Overrideables - notification handlers

Overrideable Handlers

Implementation

Keeping OnOpenAFolder in the implementation file means that we don't need to include ScopeGuard.h in the header.

Override

Overrideables

Return option character just processed by GetOpt().

The compiler will automatically inline if /Ob2 is on, so we'll ask anyways.

Methods call this one to handle keyboard message for ActiveX controls

if we pass horizontal by reference, compiler produces [horrible pointer code] for `if ( horizontal )`, pass by value generates `test r15b, r15b`

IUnknown methods

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