Add {Lock,Unlock,Show,Hide}Cursor() to the window manager mojom.

ash/shell_port.h

Index: ash/shell_port.h
diff --git a/ash/shell_port.h b/ash/shell_port.h
index 1daaeeb70a6c53a02bcb58a1ff4da2061bafb2b4..f91f2e80172239c7f96684af8571123152cd00bf 100644
--- a/ash/shell_port.h
+++ b/ash/shell_port.h
@@ -15,6 +15,8 @@
 #include "ash/metrics/user_metrics_action.h"
 #include "ash/wm/lock_state_observer.h"
 #include "base/observer_list.h"
+#include "base/optional.h"
+#include "ui/base/cursor/cursor_data.h"
 #include "ui/base/ui_base_types.h"
 #include "ui/compositor/layer_type.h"
 #include "ui/wm/public/activation_change_observer.h"
@@ -134,6 +136,10 @@ class ASH_EXPORT ShellPort {
   // See aura::client::CursorClient for details on these.
   virtual void LockCursor() = 0;
   virtual void UnlockCursor() = 0;
+  virtual void ShowCursor() = 0;
+  virtual void HideCursor() = 0;
+  virtual void SetGlobalOverrideCursor(
+      base::Optional<ui::CursorData> cursor) = 0;
   virtual bool IsMouseEventsEnabled() = 0;
 
   virtual std::vector<WmWindow*> GetAllRootWindows() = 0;