Do not start or unpause an animation with no definition or 0 duration
Do not start or unpause an animation with no definition or 0 duration

Doing so can cause infinite loops with loop and bounce replay modes.
Reported by Jordan Weber, thanks!

RealityFactory/CEGUI,RealityFactory/CEGUI,arkana-fts/cegui,arkana-fts/cegui,cbeck88/cegui-mirror,cbeck88/cegui-mirror,arkana-fts/cegui,arkana-fts/cegui,RealityFactory/CEGUI,RealityFactory/CEGUI,arkana-fts/cegui,RealityFactory/CEGUI,cbeck88/cegui-mirror,cbeck88/cegui-mirror,cbeck88/cegui-mirror