decode: don't clobber encoder's reconstructed output
decode: don't clobber encoder's reconstructed output

jmvalin/daala,HeadhunterXamd/daala,luctrudeau/daala,KyleSiefring/daala,xiph/daala,HeadhunterXamd/daala,xiphmont/daala,HeadhunterXamd/daala,xiph/daala,ycho/daala,ycho/daala,luctrudeau/daala,luctrudeau/daala,jmvalin/daala,KyleSiefring/daala,xiphmont/daala,jmvalin/daala,ycho/daala,KyleSiefring/daala,jmvalin/daala,HeadhunterXamd/daala,xiph/daala,ycho/daala,xiphmont/daala,KyleSiefring/daala,HeadhunterXamd/daala,jmvalin/daala,xiphmont/daala,ycho/daala,xiph/daala,xiph/daala,xiphmont/daala,KyleSiefring/daala,luctrudeau/daala,luctrudeau/daala