const runtime.waitReasonGarbageCollectionScan

4 uses

	runtime (current package)
		mgcmark.go#L220: 				casGToWaitingForGC(userG, _Grunning, waitReasonGarbageCollectionScan)
		runtime2.go#L1069: 	waitReasonGarbageCollectionScan                   // "garbage collection scan"
		runtime2.go#L1110: 	waitReasonGarbageCollectionScan: "garbage collection scan",
		runtime2.go#L1170: 	waitReasonGarbageCollectionScan: true,