Fix for crash when using high bitdepth and var-tx
Fix for crash when using high bitdepth and var-tx

Change-Id: Ide48fa4312f7828f99290f7a2be878f5673fa716

luctrudeau/aom,GrokImageCompression/aom,smarter/aom,luctrudeau/aom,mbebenita/aom,GrokImageCompression/aom,GrokImageCompression/aom,luctrudeau/aom,smarter/aom,mbebenita/aom,mbebenita/aom,smarter/aom,GrokImageCompression/aom,mbebenita/aom,GrokImageCompression/aom,smarter/aom,smarter/aom,smarter/aom,luctrudeau/aom,mbebenita/aom,mbebenita/aom,luctrudeau/aom,mbebenita/aom,luctrudeau/aom,mbebenita/aom,mbebenita/aom,GrokImageCompression/aom