Remove Worker.worked, it was too heavy to be run always

Also move update of Worker.total to run-one
- so we don't lose any completions not seen by supervisor yet at end

src/core/ThreadPoolScheduler.pm

@@ -202,9 +202,6 @@ my class ThreadPoolScheduler does Scheduler {
         # Total number of tasks completed since creation.
         has int $.total;
 
-        # Wallclock seconds actually worked
-        has num $.worked;
-
         # Working is 1 if the worker is currently busy, 0 if not.
         has int $.working;
 
@@ -225,26 +222,20 @@ my class ThreadPoolScheduler does Scheduler {
                 ++$!times-nothing-completed;
             }
             else {
-                $!total = $!total + $taken;
                 $!times-nothing-completed = 0;
             }
             $taken
         }
 
         method !run-one(\task --> Nil) {
-            my num $start;
             $!working = 1;
             nqp::continuationreset(THREAD_POOL_PROMPT, {
                 if nqp::istype(task, List) {
                     my Mu $code := nqp::shift(nqp::getattr(task, List, '$!reified'));
-                    $start = nqp::time_n;
                     $code(|task);
-                    $!worked = nqp::add_n($!worked,nqp::sub_n(nqp::time_n,$start));
                 }
                 else {
-                    $start = nqp::time_n;
                     task.();
-                    $!worked = nqp::add_n($!worked,nqp::sub_n(nqp::time_n,$start));
                 }
                 CONTROL {
                     default {
@@ -265,6 +256,7 @@ my class ThreadPoolScheduler does Scheduler {
 #?if !moar
             ++$!completed;
 #?endif
+            ++$!total;
         }
     }
     my class GeneralWorker does Worker {