Turn off log spew, and make it use Slog.w instead of e.printStackTrace

That said, it's happening.

system     04-26 17:01:43.344 1000   1140   2684   W/ActivityManager: Failed setting process group of 21751 to 0
main       04-26 17:01:43.344 1000   1140   2684   W/System.err: java.lang.IllegalArgumentException: Given thread 21496 does not exist
main       04-26 17:01:43.349 1000   1140   2684   W/System.err:    at android.os.Process.setThreadPriority(Native Method)
main       04-26 17:01:43.349 1000   1140   2684   W/System.err:    at com.android.server.am.ActivityManagerService.applyOomAdjLocked(ActivityManagerService.java:21704)
main       04-26 17:01:43.349 1000   1140   2684   W/System.err:    at com.android.server.am.ActivityManagerService.updateOomAdjLocked(ActivityManagerService.java:22015)
main       04-26 17:01:43.349 1000   1140   2684   W/System.err:    at com.android.server.am.ActivityManagerService.updateOomAdjLocked(ActivityManagerService.java:22093)
main       04-26 17:01:43.349 1000   1140   2684   W/System.err:    at com.android.server.am.ActiveServices.unbindServiceLocked(ActiveServices.java:1239)
main       04-26 17:01:43.349 1000   1140   2684   W/System.err:    at com.android.server.am.ActivityManagerService.unbindService(ActivityManagerService.java:18127)
main       04-26 17:01:43.349 1000   1140   2684   W/System.err:    at android.app.IActivityManager$Stub.onTransact(IActivityManager.java:594)
main       04-26 17:01:43.349 1000   1140   2684   W/System.err:    at com.android.server.am.ActivityManagerService.onTransact(ActivityManagerService.java:2936)
main       04-26 17:01:43.350 1000   1140   2684   W/System.err:    at android.os.Binder.execTransact(Binder.java:674)

Bug: 37252687
Test: development/tools/logblame/app_switch_log_test
Change-Id: I138147c34141e212256012afe8aaf239f3443b82