Fix use after free for cached_displays_.

ui/ozone/platform/drm/host/drm_display_host_manager.cc

Index: ui/ozone/platform/drm/host/drm_display_host_manager.cc
diff --git a/ui/ozone/platform/drm/host/drm_display_host_manager.cc b/ui/ozone/platform/drm/host/drm_display_host_manager.cc
index ee34f677f4dd3a0da14340ffc6db2841b0123be6..edc62b64d21308e809b7e8eb97e76505e0baaa11 100644
--- a/ui/ozone/platform/drm/host/drm_display_host_manager.cc
+++ b/ui/ozone/platform/drm/host/drm_display_host_manager.cc
@@ -359,6 +359,8 @@ void DrmDisplayHostManager::OnGpuThreadRetired() {}
 
 void DrmDisplayHostManager::GpuHasUpdatedNativeDisplays(
     const std::vector<DisplaySnapshot_Params>& params) {
+  if (delegate_)
+    delegate_->OnDisplaySnapshotsInvalidated();
   std::vector<std::unique_ptr<DrmDisplayHost>> old_displays;
   displays_.swap(old_displays);
   for (size_t i = 0; i < params.size(); ++i) {