Folds methods in WmShellCommon to WmShell

ash/common/wm/overview/window_selector_controller.cc

Index: ash/common/wm/overview/window_selector_controller.cc
diff --git a/ash/common/wm/overview/window_selector_controller.cc b/ash/common/wm/overview/window_selector_controller.cc
index 21362f851fd76a268f551623615c3c21eeb1dbea..265c8bd43d00ed7870e0208da2f6069d4ee33d06 100644
--- a/ash/common/wm/overview/window_selector_controller.cc
+++ b/ash/common/wm/overview/window_selector_controller.cc
@@ -44,7 +44,7 @@ void WindowSelectorController::ToggleOverview() {
       return;
 
     std::vector<WmWindow*> windows =
-        WmShell::Get()->GetMruWindowTracker()->BuildMruWindowList();
+        WmShell::Get()->mru_window_tracker()->BuildMruWindowList();
     auto end =
         std::remove_if(windows.begin(), windows.end(),
                        std::not1(std::ptr_fun(&WindowSelector::IsSelectable)));