mash: remove more shell/shelf WmWindow usage.

ash/metrics/user_metrics_recorder.cc

Index: ash/metrics/user_metrics_recorder.cc
diff --git a/ash/metrics/user_metrics_recorder.cc b/ash/metrics/user_metrics_recorder.cc
index a28b656b04e519a80ca18e49b0ffbeefb579d6c1..d9c216c888a32123ed38021d0e7529fee464d5a0 100644
--- a/ash/metrics/user_metrics_recorder.cc
+++ b/ash/metrics/user_metrics_recorder.cc
@@ -14,7 +14,6 @@
 #include "ash/shelf/shelf_view.h"
 #include "ash/shelf/wm_shelf.h"
 #include "ash/shell.h"
-#include "ash/shell_port.h"
 #include "ash/wm/window_state.h"
 #include "ash/wm/window_state_aura.h"
 #include "ash/wm_window.h"
@@ -626,7 +625,7 @@ void UserMetricsRecorder::OnShellShuttingDown() {
 }
 
 void UserMetricsRecorder::RecordPeriodicMetrics() {
-  WmShelf* shelf = WmShelf::ForWindow(ShellPort::Get()->GetPrimaryRootWindow());
+  WmShelf* shelf = WmShelf::ForWindow(Shell::GetPrimaryRootWindow());
   // TODO(bruthig): Investigating whether the check for |manager| is necessary
   // and add tests if it is.
   if (shelf) {