ozone: evdev: Don't crash without cursor in scroll & click events

ui/events/ozone/evdev/libgestures_glue/gesture_interpreter_libevdev_cros.cc

Index: ui/events/ozone/evdev/libgestures_glue/gesture_interpreter_libevdev_cros.cc
diff --git a/ui/events/ozone/evdev/libgestures_glue/gesture_interpreter_libevdev_cros.cc b/ui/events/ozone/evdev/libgestures_glue/gesture_interpreter_libevdev_cros.cc
index 503155a7c4396e7fb6801b0c4131a3cfd638b25a..11dd2d71fa5d5583b6e407b83d86bd2fe2f8b7bc 100644
--- a/ui/events/ozone/evdev/libgestures_glue/gesture_interpreter_libevdev_cros.cc
+++ b/ui/events/ozone/evdev/libgestures_glue/gesture_interpreter_libevdev_cros.cc
@@ -209,6 +209,8 @@ void GestureInterpreterLibevdevCros::OnGestureMove(const Gesture* gesture,
 void GestureInterpreterLibevdevCros::OnGestureScroll(
     const Gesture* gesture,
     const GestureScroll* scroll) {
+  if (!cursor_)
+    return;  // No cursor!
   DVLOG(3) << base::StringPrintf("Gesture Scroll: (%f, %f) [%f, %f]",
                                  scroll->dx,
                                  scroll->dy,
@@ -255,6 +257,8 @@ void GestureInterpreterLibevdevCros::Dispatch(Event* event) {
 
 void GestureInterpreterLibevdevCros::DispatchMouseButton(unsigned int modifier,
                                                          bool down) {
+  if (!cursor_)
+    return;  // No cursor!
   const gfx::PointF& loc = cursor_->location();
   int flag = modifiers_->GetEventFlagFromModifier(modifier);
   EventType type = (down ? ET_MOUSE_PRESSED : ET_MOUSE_RELEASED);