Remove stale cb arg on xhr
Remove stale cb arg on xhr

0x90sled/catapult,vmpstr/trace-viewer,0x90sled/catapult,SummerLW/Perf-Insight-Report,catapult-project/catapult-csm,dstockwell/catapult,danbeam/catapult,modulexcite/catapult,danbeam/catapult,catapult-project/catapult-csm,scottmcmaster/catapult,benschmaus/catapult,SummerLW/Perf-Insight-Report,dstockwell/catapult,dstockwell/catapult,benschmaus/catapult,dstockwell/catapult,danbeam/catapult,catapult-project/catapult,catapult-project/catapult-csm,benschmaus/catapult,zeptonaut/catapult,SummerLW/Perf-Insight-Report,danbeam/catapult,sahiljain/catapult,sahiljain/catapult,vmpstr/trace-viewer,SummerLW/Perf-Insight-Report,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,scottmcmaster/catapult,catapult-project/catapult,0x90sled/catapult,vmpstr/trace-viewer,benschmaus/catapult,catapult-project/catapult-csm,catapult-project/catapult-csm,SummerLW/Perf-Insight-Report,benschmaus/catapult,sahiljain/catapult,scottmcmaster/catapult,modulexcite/catapult,zeptonaut/catapult,sahiljain/catapult,sahiljain/catapult,sahiljain/catapult,benschmaus/catapult,catapult-project/catapult-csm,zeptonaut/catapult,catapult-project/catapult,SummerLW/Perf-Insight-Report,catapult-project/catapult-csm,catapult-project/catapult,benschmaus/catapult,modulexcite/catapult