Fix Android build errors
Fix Android build errors

br111an/oxyplot,mattleibow/oxyplot,HermanEldering/oxyplot,freudenthal/oxyplot,lynxkor/oxyplot,olegtarasov/oxyplot,oxyplot/oxyplot,HermanEldering/oxyplot,Jofta/oxyplot,Kaplas80/oxyplot,olegtarasov/oxyplot,bbqchickenrobot/oxyplot,GeertvanHorrik/oxyplot,freudenthal/oxyplot,bbqchickenrobot/oxyplot,shoelzer/oxyplot,as-zhuravlev/oxyplot_wpf_fork,mattleibow/oxyplot,Mitch-Connor/oxyplot,shoelzer/oxyplot,GeertvanHorrik/oxyplot,Isolocis/oxyplot,jeremyiverson/oxyplot,svendu/oxyplot,Kaplas80/oxyplot,as-zhuravlev/oxyplot_wpf_fork,objorke/oxyplot,Sbosanquet/oxyplot,br111an/oxyplot,freudenthal/oxyplot,br111an/oxyplot,Rustemt/oxyplot,Jonarw/oxyplot,Mitch-Connor/oxyplot,Rustemt/oxyplot,as-zhuravlev/oxyplot_wpf_fork,shoelzer/oxyplot,svendu/oxyplot,ze-pequeno/oxyplot,Sbosanquet/oxyplot,H2ONaCl/oxyplot,lynxkor/oxyplot,Rustemt/oxyplot,Sbosanquet/oxyplot,GeertvanHorrik/oxyplot,Mitch-Connor/oxyplot,objorke/oxyplot,lynxkor/oxyplot,TheAlmightyBob/oxyplot,DotNetDoctor/oxyplot,jeremyiverson/oxyplot,svendu/oxyplot,H2ONaCl/oxyplot,zur003/oxyplot,bbqchickenrobot/oxyplot,TheAlmightyBob/oxyplot,DotNetDoctor/oxyplot,NilesDavis/oxyplot,objorke/oxyplot,jeremyiverson/oxyplot,H2ONaCl/oxyplot,TheAlmightyBob/oxyplot