wxXmlResourceHandlerImplBase::GetAnimation() returned wxAnimation by value
which created references to wxAnimationCtrlNameStr and wxNullAnimation
symbols, defined in the "adv" library, in "core" when using Sun CC even though
they were not referenced directly.
Fix this by returning wxAnimation by pointer to keep it opaque for "core" code.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72782 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Split wxXmlResourceHandler into an ABC and the real implementation to allow
referencing the ABC in the core library itself but without pulling in all of
the XRC into it. This also allows defining XRC handlers, which only depend on
this ABC and not the xrc library, in other libraries, such as richtext, as
demonstrated by the now enabled wxRichTextXMLHandler.
Closes#10996.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72727 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
