Revert "[test] Be more chatty when killing hanging tests"

This reverts commit fad1c1c9.

Reason for revert: Debug printing not needed anymore.

Original change's description:
> [test] Be more chatty when killing hanging tests
> 
> Bug: v8:8292
> Change-Id: I74fd304692e90adfb694b73ecf5e7858e3b66607
> Reviewed-on: https://chromium-review.googlesource.com/c/1275814
> Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
> Reviewed-by: Maya Lekova <mslekova@chromium.org>
> Commit-Queue: Michael Achenbach <machenbach@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#56562}

TBR=machenbach@chromium.org,sergiyb@chromium.org,mslekova@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: v8:8292
Change-Id: Ieaba51f866b93d49fe168b6370bd126752993afb
Reviewed-on: https://chromium-review.googlesource.com/c/1288632Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56774}

tools/testrunner/local/command.py

@@ -127,15 +127,9 @@ class BaseCommand(object):
   def _abort(self, process, abort_called):
     abort_called[0] = True
     try:
-      print 'Attempting to kill process %d' % process.pid
-      sys.stdout.flush()
       self._kill_process(process)
-      print 'Attempted to kill process %d' % process.pid
-      sys.stdout.flush()
-    except OSError as e:
-      print 'Error killing process %d' % process.pid
-      print e
-      sys.stdout.flush()
+    except OSError:
+      pass
 
   def __str__(self):
     return self.to_string()
@@ -192,6 +186,9 @@ class WindowsCommand(BaseCommand):
     return subprocess.list2cmdline(self._to_args_list())
 
   def _kill_process(self, process):
+    if self.verbose:
+      print 'Attempting to kill process %d' % process.pid
+      sys.stdout.flush()
     tk = subprocess.Popen(
         'taskkill /T /F /PID %d' % process.pid,
         stdout=subprocess.PIPE,