Add name to threads

This help identifying threads when debugging.
The naming scheme is using 'class/function name + variable name'.
Note that the length limitaion is 16 chars on linux. On Windows, the limit is 32767 chars.

PR #21403.

src/base/bittorrent/bencoderesumedatastorage.h

@@ -37,7 +37,6 @@
 #include "resumedatastorage.h"
 
 class QByteArray;
-class QThread;
 
 namespace BitTorrent
 {