[overlay] Fix CMTimeRange.isValid
[overlay] Fix CMTimeRange.isValid

<rdar://problem/30576556>

zisko/swift,hooman/swift,uasys/swift,karwa/swift,OscarSwanros/swift,aschwaighofer/swift,parkera/swift,parkera/swift,felix91gr/swift,austinzheng/swift,jopamer/swift,xedin/swift,xwu/swift,xedin/swift,xedin/swift,huonw/swift,deyton/swift,return/swift,alblue/swift,OscarSwanros/swift,practicalswift/swift,tjw/swift,lorentey/swift,frootloops/swift,gribozavr/swift,xedin/swift,karwa/swift,rudkx/swift,shahmishal/swift,zisko/swift,rudkx/swift,shajrawi/swift,glessard/swift,hooman/swift,jopamer/swift,huonw/swift,karwa/swift,gregomni/swift,huonw/swift,benlangmuir/swift,atrick/swift,aschwaighofer/swift,shahmishal/swift,shahmishal/swift,tjw/swift,alblue/swift,jmgc/swift,milseman/swift,jtbandes/swift,airspeedswift/swift,jopamer/swift,tjw/swift,lorentey/swift,karwa/swift,swiftix/swift,devincoughlin/swift,frootloops/swift,alblue/swift,allevato/swift,jmgc/swift,parkera/swift,apple/swift,alblue/swift,benlangmuir/swift,jckarter/swift,danielmartin/swift,parkera/swift,devincoughlin/swift,Jnosh/swift,devincoughlin/swift,ahoppen/swift,practicalswift/swift,frootloops/swift,milseman/swift,deyton/swift,jopamer/swift,amraboelela/swift,airspeedswift/swift,benlangmuir/swift,CodaFi/swift,sschiau/swift,felix91gr/swift,zisko/swift,shajrawi/swift,tkremenek/swift,milseman/swift,zisko/swift,hooman/swift,stephentyrone/swift,huonw/swift,huonw/swift,gribozavr/swift,jtbandes/swift,Jnosh/swift,amraboelela/swift,djwbrown/swift,frootloops/swift,atrick/swift,parkera/swift,gribozavr/swift,tkremenek/swift,xwu/swift,OscarSwanros/swift,harlanhaskins/swift,sschiau/swift,natecook1000/swift,OscarSwanros/swift,karwa/swift,shahmishal/swift,jmgc/swift,parkera/swift,shajrawi/swift,alblue/swift,jckarter/swift,apple/swift,lorentey/swift,jtbandes/swift,jopamer/swift,jtbandes/swift,austinzheng/swift,rudkx/swift,roambotics/swift,huonw/swift,shahmishal/swift,airspeedswift/swift,harlanhaskins/swift,JGiola/swift,stephentyrone/swift,milseman/swift,shajrawi/swift,natecook1000/swift,return/swift,deyton/swift,calebd/swift,tjw/swift,felix91gr/swift,djwbrown/swift,danielmartin/swift,harlanhaskins/swift,shahmishal/swift,zisko/swift,devincoughlin/swift,allevato/swift,nathawes/swift,allevato/swift,apple/swift,uasys/swift,xwu/swift,danielmartin/swift,shajrawi/swift,swiftix/swift,tjw/swift,stephentyrone/swift,airspeedswift/swift,glessard/swift,roambotics/swift,natecook1000/swift,xedin/swift,benlangmuir/swift,devincoughlin/swift,zisko/swift,gregomni/swift,allevato/swift,gregomni/swift,milseman/swift,Jnosh/swift,JGiola/swift,milseman/swift,practicalswift/swift,lorentey/swift,gribozavr/swift,swiftix/swift,jckarter/swift,lorentey/swift,jopamer/swift,JGiola/swift,hughbe/swift,amraboelela/swift,Jnosh/swift,swiftix/swift,nathawes/swift,allevato/swift,danielmartin/swift,parkera/swift,uasys/swift,roambotics/swift,atrick/swift,danielmartin/swift,lorentey/swift,aschwaighofer/swift,JGiola/swift,roambotics/swift,nathawes/swift,austinzheng/swift,CodaFi/swift,practicalswift/swift,xwu/swift,calebd/swift,rudkx/swift,tkremenek/swift,shajrawi/swift,danielmartin/swift,OscarSwanros/swift,brentdax/swift,apple/swift,djwbrown/swift,ahoppen/swift,practicalswift/swift,tjw/swift,allevato/swift,danielmartin/swift,uasys/swift,tjw/swift,gribozavr/swift,gregomni/swift,gribozavr/swift,OscarSwanros/swift,hooman/swift,airspeedswift/swift,karwa/swift,glessard/swift,ahoppen/swift,devincoughlin/swift,CodaFi/swift,zisko/swift,karwa/swift,felix91gr/swift,practicalswift/swift,gribozavr/swift,tkremenek/swift,practicalswift/swift,djwbrown/swift,lorentey/swift,parkera/swift,glessard/swift,calebd/swift,hughbe/swift,milseman/swift,jtbandes/swift,shahmishal/swift,frootloops/swift,aschwaighofer/swift,amraboelela/swift,natecook1000/swift,sschiau/swift,xedin/swift,brentdax/swift,jopamer/swift,nathawes/swift,lorentey/swift,sschiau/swift,allevato/swift,return/swift,austinzheng/swift,karwa/swift,glessard/swift,airspeedswift/swift,tkremenek/swift,CodaFi/swift,amraboelela/swift,sschiau/swift,uasys/swift,swiftix/swift,atrick/swift,austinzheng/swift,xedin/swift,natecook1000/swift,harlanhaskins/swift,sschiau/swift,nathawes/swift,CodaFi/swift,djwbrown/swift,swiftix/swift,frootloops/swift,sschiau/swift,rudkx/swift,hughbe/swift,jckarter/swift,apple/swift,gregomni/swift,jmgc/swift,practicalswift/swift,atrick/swift,return/swift,aschwaighofer/swift,harlanhaskins/swift,brentdax/swift,jtbandes/swift,shahmishal/swift,brentdax/swift,hughbe/swift,brentdax/swift,benlangmuir/swift,ahoppen/swift,devincoughlin/swift,return/swift,rudkx/swift,djwbrown/swift,xedin/swift,return/swift,hughbe/swift,OscarSwanros/swift,tkremenek/swift,roambotics/swift,deyton/swift,austinzheng/swift,hooman/swift,hughbe/swift,xwu/swift,brentdax/swift,ahoppen/swift,JGiola/swift,nathawes/swift,benlangmuir/swift,stephentyrone/swift,natecook1000/swift,hooman/swift,calebd/swift,shajrawi/swift,JGiola/swift,gregomni/swift,calebd/swift,nathawes/swift,deyton/swift,xwu/swift,alblue/swift,felix91gr/swift,calebd/swift,xwu/swift,Jnosh/swift,hughbe/swift,sschiau/swift,stephentyrone/swift,frootloops/swift,alblue/swift,jmgc/swift,natecook1000/swift,uasys/swift,atrick/swift,glessard/swift,devincoughlin/swift,Jnosh/swift,calebd/swift,harlanhaskins/swift,amraboelela/swift,stephentyrone/swift,aschwaighofer/swift,amraboelela/swift,jmgc/swift,swiftix/swift,return/swift,harlanhaskins/swift,deyton/swift,gribozavr/swift,jmgc/swift,jckarter/swift,huonw/swift,jckarter/swift,djwbrown/swift,jtbandes/swift,ahoppen/swift,austinzheng/swift,stephentyrone/swift,felix91gr/swift,Jnosh/swift,deyton/swift,tkremenek/swift,brentdax/swift,felix91gr/swift,jckarter/swift,apple/swift,CodaFi/swift,shajrawi/swift,hooman/swift,airspeedswift/swift,roambotics/swift,CodaFi/swift,uasys/swift,aschwaighofer/swift